Sunny Afternoon - Twilight - Moonlight - Electrical Candlelight - Underwater
3D environment
lighting
‘3D Environment Lighting’ is a 6-part tutorial
series. Over the course of the six chapters, this
series will be detailing techniques on lighting
an environment under a number of different
conditions. Each chapter we will cover a
step-by-step guide to setting up lights, aimed
at portraying the scene in a specific manner.
The various chapters will be tailored to specific
software packages and each will aim to show
a comprehensive and effective way of lighting
an interior of a ship that includes both natural
and artificial light. These will include a sunny
afternoon, sunset, moonlight, electric light,
candle light, and finally a submerged submarine
light. The schedule is as follows:
Chapter 01
Natural Exterior Lighting
Sunny Afternoon
Chapter 02
Natural Exterior Lighting
Twilight
Chapter 03
Natural Exterior Lighting
Moonlight
Chapter 04
Artificial Interior Lighting
Electrical
Chapter 05
Artificial Interior Lighting
Candlelight
Chapter 06
Artificial Interior Lighting
Underwater
Chapter 01
Natural Exterior Lighting
Sunny Afternoon
Chapter 01 Sunny Afternoon
Natural Exterior Lighting
Fig 01
Sunny Afternoon
This tutorial is intended to be used with
Autodesk Maya 8.5.
Welcome to the first of the six-part tutorial
series, discussing possibly the most challenging
kind of 3D environment: interiors. Mental Ray
(for Maya) users typically get cold feet and
sweating fingers when it comes to this “closed
combat”; the royal league of environment
lighting. It’s for no reason though, as all you
need for the battle is a simple field manual (this
tutorial), and just a little bit of patience...
So what is it all about? Set the project (Fig01)
Fig 02
to the folder you unzipped, which is called
3DEnvironment_maya (download can be found
at the end of this tutorial; click on the Free
Resources logo), and let’s have a look at our
object for this demonstration (Fig02) ...
As you can see, we have a closed room; you
can tell by the porthole and the characteristic
door that it is a room inside a ship. Let’s imagine
that it’s a tween deck of the ferry “MS No-Frills”,
used as a lounge, and the staircase leads to its
upper deck.
From a lighter’s point of view, we can estimate
by this analysis that there is light coming in
from a) the opening in the ceiling where the
Fig 03
staircase leads outside, and b) from the porthole
and the window beside it. That’s not much,
and if you ever took a photograph under such
conditions you will know that, even with nice
equipment, you would have a hard time catching
the right moment (the “magic hour”) to illustrate
the beauty of this particular atmosphere.
(Atmosphere is also defined, besides by the
lighting condition itself, by things like a point
in time, the architecture, the weather, and
occasionally also the vegetation.)
So, for our first tutorial part, we will choose the
following scenario: our ship, the MS No-Frills, is
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Environment Lighting
Sunny Afternoon Chapter 01
Fig 04
anchored somewhere along the shore of Tunisia
(North Africa) in the Mediterranean Sea; it’s
summer, the time is around early afternoon, and
the weather is nice and clear. That’s all we need
to know at this stage to get us started...
If you open up the scene, you will see that
there’s no proper point of view defined yet.
Feel free to either choose your own perspective
or use one of the bookmarks I have set in the
default perspective camera (Fig03). By clicking
on one of the bookmarks, all relevant camera
attributes (position, orientation, focal length,
etc.) are changed to the condition stored in
the bookmark. This greatly helps when trying
out different views without committing oneself,
Fig 05
and without creating an unnecessary mess of
different cameras.
Before we start lighting and rendering the
scene, we should have a little introduction to the
actual shading of the scene and about a few of
the technical aspects of things such as colour
spaces. If you find this too boring then you might
want to skip the next two paragraphs as this is
not essential, but is nonetheless an explanation
regarding how to achieve to the result at the end
of this tutorial.
A Note on Shading. All the shaders you see
are built on the new mia_material that ships
with Maya 8.5. This shader was intended as
Fig 06
a monolithic (from the Greek words “mono”,
meaning single, and “lithos”, meaning stone)
approach for architectural purposes, but can
be practically used to simulate the majority of
the common materials that we see every day.
Unlike the regular Maya shaders, and most of
the custom Mental Ray shaders, it implements
physical accuracy, greatly optimised glossy
reflections, transparency and translucency, builtin ambient occlusion for detail enhancement
of final gather solutions, automatic shadow
and photon shading, many optimisations and
performance enhancers, and the most important
thing is that it’s really easy to use. And it’s all in
one - thus “monolithic”. I therefore decided to
use it in our tutorial...
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Environment Lighting
Chapter 01 Sunny Afternoon
A Note on Colour Space. As you may already
Fig 07
know, usually all of the photographs and
pictures that you look at on your computer are
in sRGB. This is because, for example, a colour
value of RGB 200, 200, 200 is not twice as
bright as a colour with RGB 100, 100, 100, as
you would expect. It is of course mathematically
twice the value, but perceptually it is not. As
opposed to plain mathematics (like 2 x 100
= 200), our eyes do not work in such a linear
way. And here’s where the sRGB comes in...
This colour space ‘maps’ the values so that
they appear linearly. Here the RGB 200, 200,
200 is perceptually roughly twice as bright as
RGB 100, 100, 100. This is why most of the
photographs are visually pleasing and look
natural, which is not in a true mathematically
linear colour space. However, almost every
Fig 08
renderer spits out these old and truly linear
images, unless we tell them to do otherwise.
Most people are not aware of this, and
instead of rendering in the right colour space
they unnecessarily add lights and ambient
components to unwittingly compensate for
this error. In Fig04 and Fig05, you can see
two photographic examples illustrating the
difference between a true linear (left) and an
sRGB colour space (right). In Fig06, you can
see the same from a CG rendering; you’ll notice
that the true linear one looks a lot more “CGish”
and unnatural. Even if you brightened it up and
added/reduced the contrast, you still couldn’t
compensate for the fact that it’s in the wrong
colour space. This is an essential issue in order
Fig 09
to create visually pleasing and naturally looking
computer graphics. If you have followed me up
to here, and you think you understand the need
for a correct colour space, then go take a break
and get yourself some coffee or delicious green
tea and enjoy life for a while - you have earned
it! This is all tricky yet fundamental knowledge.
How this theory is practically applied in Mental
Ray will be shown later on...
So, let’s get started with lighting the scene...
Maya 8.5 introduces, along with the mia
package, a handy physical sun and sky system.
This makes it easy to set up a natural looking
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Environment Lighting
Sunny Afternoon Chapter 01
Fig 10
environment and we can then focus more on the
aesthetic part of the lighting process, instead of
tweaking odd-looking colours. The sky system
is created from the render global’s environment
tab (Fig07). By clicking on the button, you
practically create:
a) a directional light which acts as the sun’s
direction;
b) the corresponding light shader mia_
physicalsun;
c) the mia_physicalsky, an environment
shader that connects to the renderable
camera’s mental ray environment (Fig08);
d) a tone mapping lens shader called
mia_exposure_simple, which also connects to
the camera’s mental ray lens slot.
Fig 11
It’s also worth mentioning here that this button
also turns Final Gathering ON.
Now that we have a default sun and sky system
set up, we are almost ready to render. Before
we do the first test render, let’s make sure
we are in the right colour space. By default,
we are rendering in true linear space (for an
explanation please refer to the previous notes
on colour space), which is - for our needs right
now - not correct. The lens shader we created
however (Fig08) brings us into a colour space
which closely approximates sRGB by applying
a 2.2 gamma curve (see the Gamma attribute)
globally to the whole rendered image, as we
calculate it. Generally, this is a good thing and
Fig 12
is desirable. But if we apply a gamma correction
in this way, then we would have to “un-gamma”
every single texture file in our scene. This is due
to the fact that the textures already have a -2.2
gamma (this is usually true for any 8bit or 16bit
image file), and adding a gamma correction on
top of that would double the gamma and could
potentially wash out the textures’ colours. (What
a bummer!)
So, we either have to “un-gamma” every texture
file (boring and tedious), or instead of the lens
shader’s gamma correction, we can use Mental
Ray’s internal gamma correction (still boring, but
less tedious).
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Environment Lighting
Chapter 01 Sunny Afternoon
As you can see from Fig09, we set the Gamma
Fig 13
value in the Render Globals’ primary framebuffer
menu to the desired value, which is simply
because Mental Ray works this way; 1 divided
by the value (2.2 for approximating sRGB in our
case), which equals 0.455. At the same time,
we also need to remove the gamma correction
of our lens shader, so we must set its Gamma
attribute to 1.0 (linear equals no correction; you
can select these shaders from the hypershade’s
Utilities tab). Thus we completely hand over
the gamma correction to Mental Ray’s internal
mechanism, which automatically applies the
right “un-gamma” value to our textures. This is
a long-winded theory, but there are no more
worries now and we’re ready to go!
I tweaked the Final Gathering settings (Fig10)
Fig 14
so that we will get a relatively fast converging,
yet meaningful, result. I also turned down
the mia_physicalsun’s Samples to 2. It’s kind
of dark and has a few errors (Fig11), mainly
because of insufficient ray tracing settings.
Let’s now increase the general ray depths
(Fig12) and the Final Gathering ray depths
(Fig13). We’re also turning the Secondary
Diffuse Bounces On. However, the Secondary
Bounces button in the Render Globals only sets
their Bounce Depth to 1; we want it to bounce
twice so we’re selecting the actual node where
all the Mental Ray settings are stored, which
is called “miDefaultOptions”. You can do this
by typing in “miDef*” in the input line with LMB
Select by name on (the asterisk is a wildcard
Fig 15
for lazy people like me, see Fig 14). Once we
select the miDefaultOptions, all more or less
hidden Mental Ray settings are exposed to the
attribute editor. There’s also some stuff in the
mentalrayGlobals node, but we’re focusing on
the Final Gather tab in the miDefaultOptions
right now. Let’s set the FG Diffuse Bounces
attribute to 2 (Fig15). These ray depth settings
should suffice to get the result at the end of this
tutorial.
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Environment Lighting
Sunny Afternoon Chapter 01
Fig 16
Let’s re-render (Fig16). It is still pretty dark, but
you can tell that the indirect light contribution is
sufficient (don’t worry about detailed shadowing,
we’ll get to that later on), so we need to actually
raise the exposure level of our piece, somehow.
Fig 17
Remember, we’re all still on the very basic
default settings for everything. One setting used
to tweak the exposure is the Gain attribute in the
mia_exposure_simple, which is connected as
a lens shader to our camera. Let’s increase the
Gain value to 0.5 (Fig17).
Fig 18
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Page 9
That’s much better, and gives a more natural
feeling (Fig18).
Environment Lighting
Chapter 01 Sunny Afternoon
Now we can start to actually make decisions on
Fig 19
the lighting and aesthetic accentuations. For this
part, please don’t feel constrained to the settings
and colours that I choose - feel free to follow
your own ideas! I’m rotating the sunDirection to
X -70, Y 175, Z 0 to accentuate certain elements
by direct sunlight, and I’m setting the attributes
of the mia_physicalsky to the values you can
see in Fig19. I increased the Haze value to 0.5
(note that this attribute takes values up to 15, so
0.5 is rather low). Then I set the Red/Blue Shift
to 0.1, which basically means a white-balance
correction towards reddish (towards blue-ish
would be a negative value, like -0.1). I also
raised the Saturation attribute to 2.0, which is it’s
maximum value. I then made slight adjustments
to the horizon, which does not have much effect
on the global look but I experimented with
Fig 20
what we could see through the porthole and
the window. The last thing I changed was the
Ground Colour. I gave it a greenish tint because
I thought this gave it a more lagoon-like feeling,
and I think it gives the whole piece a more
interesting touch (Fig20). From my own point of
view, this is a good base for what we intended
to accomplish with the early afternoon in the
Mediterranean Sea scenario.
If we’re satisfied with the general look, we
can then go about setting up the scene for a
Fig 21
final render. Firstly, let’s increase the Final
Gathering quality, because we can reuse the
Final Gathering solution later on. As you can
see from Fig.21, I raised the Accuracy to 64, but
more importantly, and especially for the shadow
details, the Point Density is now at 2.0. With a
denser Final Gathering solution we can also
raise the Point Interpolation without losing too
much shadowing contrast. I also set the Rebuild
setting to Off, because the lighting condition is
not changing from now on and we can therefore
re-use existing Final Gather points.
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Environment Lighting
Sunny Afternoon Chapter 01
Fig 22
Let’s have a look (Fig22). As you can see, there
is still a lack of detail in the shadowed areas,
especially in the door region (Fig.22). We can
easily get around this with the new mia_
materials which implement a special Ambient
Occlusion mode. You only need to check On for
Ambient Occlusion in the shaders, as everything
else is already set up fairly well by default (all I
did was set the Distance to a reasonable value
and darkened the Dark colour a little).
Fig 23
The main trick is the Details button in the
mia_material (leaving the Ambient at full black).
By turning on the Details mode, the Ambient
Occlusion only darkens the indirect illumination
in problem-areas, avoiding the traditional global
and unpleasant Ambient Occlusion look. See
Fig23 with the enhanced details.
Fig 24
Note: to adjust the shaders all at once, select all
mia_materials from the hypershade, and set the
Ao_on attribute in the attribute spread sheet to 1
(Fig24) (the attribute spread sheet can be found
under Window > General Editors > Attribute
Spread Sheet). Also note that switching on the
Ambient Occlusion in the shader scraps the
Final Gathering solution; it will be recalculated
from scratch. If you find the Final Gathering
taking too long, turn the Point Density down to
1.0 or 0.5, as this still gives you nice results but
the lighting details will suffer.
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Environment Lighting
Chapter 01 Sunny Afternoon
Now let’s increase the general sampling quality
Fig 25
(Fig25). The sample level is now at Min 0 and
Max 2, with contrast at 0.05 and the Filter set to
Mitchell for a sharp image.
Last but not least, if you are having problems
with artifacts caused by the glossy reflections,
raise the mia_material’s Reflection Gloss
Samples (Refl_gloss_samples) up to 8 for
superior quality. You can do this with the
attribute spread sheet, as well.
For the final render, I chose to render to a 32bit
floating point framebuffer, with a square 1024px
Fig 26
resolution. This can be set in the Render
Globals (Fig26).
If I want to have the 32bit framebuffer right out
of the GUI (without batch rendering), I need to
Fig 27
turn the Preview Convert Tiles option On and
turn the Preview Tonemap Tiles option Off, in
the Preview tab of the Render Globals (Fig27).
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Environment Lighting
Sunny Afternoon Chapter 01
Fig 28
Important: I also need to choose an appropriate
image format. OpenEXR is capable of floating
point formats and it’s widely used nowadays, so
let’s go for that (Fig28).
When rendering to the 32bit image, you will get
some funky colours in your render view, but
the resulting image will be alright - don’t worry.
After rendering, you can find it in your projects
images\tmp folder.
Fig 29
Fig 30
Fig.29 shows my final result: a pretty good base
for the post production work.
Since we rendered to a true 32bit image, we
have great freedom for possibilities. See Fig30
for my final interpretation where there is no
additional painting, only colour enhancement.
Try it for yourself!
I hope you have enjoyed following this tutorial
as much as I enjoyed writing it!
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Environment Lighting
Originally designed & modelled by:
Richard Tilbury
Tutorial by:
Florian Wild
For more from this artist visit:
http://individual.floze.de/
Or contact them:
mymail@floze.de
Chapter 02 Twilight
Chapter 02
Natural Exterior Lighting
Twilight
Twilight Chapter 02
Natural Exterior Lighting
Fig 01
Twilight
Welcome back aboard to the second part of
the Environment Lighting series for Autodesk
Maya 8.5. Again, we will be using Mental Ray
for Maya for this challenging interior illumination,
so all you need for this is to get your CPU at
operating temperature and the basic Maya
scene of our ship’s interior (download can be
found at the end of this tutorial; click on the Free
Resources logo).
Before we can start, we need to properly set the
project (Fig01). If you’re not familiar with the use
of projects, you might want to know that (one of)
the main reasons for doing this is because of
Fig 02
the relative texture paths that Maya uses. These
relative paths ensure that we can import the
scene from one file location (e.g. my computer)
to another (your computer) without any hassle,
as opposed to absolute paths which would
always point to a static location that might differ
from system to system.
So we’re back aboard the MS No-Frills, still
anchored somewhere in the Mediterranean Sea
(Fig02). For this second tutorial, we will set our
goals for accomplishing a twilight atmosphere,
which would usually occur at either dusk or
dawn.
Before we actually look at the scene, let’s take
Fig 03
a few moments to think about this very special
situation (you might want to skip or come back
later to this paragraph if you want to go straight
to the execution). Twilight, from a technical
point of view, is the time (usually around half
an hour) before sunrise or after sunset. In this
condition the sun itself is not visible; the sun’s
light is however scattered towards the observer
in the high layers of the atmosphere, either by
the air itself (Rayleigh-scattering) or aerosols.
This scattering effect causes the beautiful and
different colours that we enjoy every dusk or
dawn. From an artistic point of view, twilight
may happen in a variety of occasions, for
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Environment Lighting
Chapter 02 Twilight
Fig 04
example in stormy weather, or when natural
and artificial light sources meet - typically,
whenever two (thus “twi”) light sources or light
conditions compete for predominance. (Imagine
two wrestlers intensely fighting on the floor, and
it’s absolutely impossible to tell who’s going to
win the fight.) Twilight always has this dramatic
sense to it, and often the dramatic colours as
well. In the case of a storm, they might even
range from greenish to deep blue. Usually, in
the case of dusk and dawn, colours range from
blue to purple, and from yellow to orange and
red. The crux is that these colours are mostly
equally dominant (and therefore leave us with
great artistic and interpretational freedom),
as opposed to any other lighting condition
Fig 05
where there is usually one light source which
is predominant. With this in mind, we are now
ready to simulate the very particular case of
twilight...
We will use the same base scene as used
for part 1 of this tutorial (Sunny Afternoon),
so all shaders and textures are ready to
rumble. All surface shaders are made from the
mia_material that ships with Maya 8.5. (You
might want to read back to the Note on Shading
featured in part 1 - Sunny Afternoon - which
explains it’s basic functionality.)
Again, we are using the newly introduced
physical sun and sky system, which can easily
Fig 06
be created from the Render Globals (Fig03).
This button saves us time setting up all the
nodes and connections to make the system
work properly (thus it also turns Final Gathering
On). It basically consists of three things: the
sun, whose direction we control using the
directional light (called sunDirection, by default)
with it’s light shader mia_physicalsun; the
sky, which consists of an environment shader
(mia_physicalsky) connected to the camera; and
a simple, yet effective, so-called tonemapper
(mia_exposure_simple), used as a lens shader
on the camera (Fig04).
Before we start rendering, let’s firstly think
about a reasonable sun direction that would
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Environment Lighting
Twilight Chapter 02
fit our needs for twilight. It is very tempting to
Fig 07
actually use an angle that leaves the sun below
the horizon line, however this would yield a
diffuse and so the lighting wouldn’t be very
dramatic. You might want to experiment with
this a little, but I have decided to have a more
visible indication of where the sun actually is. I
rotated the sun on X 12.0, Y 267.0, Z 0.0; this
makes the direct sunlight shine through the
back windows, still providing a very flat angle.
There’s still one important point that we should
consider before pushing the render button: the
colour space. As already explained in the Note
on the Colour Space in the first tutorial (Sunny
Afternoon), we should make sure we work in a
correct space, which is sRGB, or in our case an
sRGB closely approximating 2.2 gamma curve.
Fig 08
The mia_exposure_simple already puts us
into this space by default (the Gamma feature
defaults to 2.2), but by doing it this way we
double the gamma on our textures files, which
by default are already in sRGB. That’s a big
secret that no-one may have ever told you
before, but trust me - it’s like that. So we either
need to remove the gamma from our textures
(“linearize” them) before rendering, which can
be done with a gammaCorrect node in front
of them in the shader chain with Gamma set
to 1/2.2, which is 0.455 rounded, or we can
use Mental Ray’s internal gamma correction
mechanism - which I prefer. So we abandon
the mia_exposure_simple’s gamma correction,
simply by setting it’s Gamma attribute to 1.0,
Fig 09
and enable Mental Ray’s mechanism by setting
the primary framebuffer’s Gamma to 1/2.2 =
0.455, in the Render Globals, as you can see in
Fig06.
So we’re ready to go and do the first test
rendering (Fig07). As you can see, the scene
is pretty dark and has a few errors caused by
the insufficient ray depths. However, we are still
using the Render Globals default Draft quality
preset...
Let’s now increase the raytracing depths to a
reasonable amount (Fig08). The values you see
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Environment Lighting
Chapter 02 Twilight
Fig 10
in Fig08 should satisfy our requirements; we
might increase the reflection depth later on...
I also tweaked the Final Gathering settings
to a lower quality (Fig09). This way, we get
a fast converging - yet meaningful - indirect
illumination for our preview renders. But
besides lowering the general Final Gathering
quality, I increased it’s trace depths and, more
importantly, turned the Secondary Diffuse
Bounces button On. This button however only
gives us a single bounce of diffuse light, as
that’s how they designed the Render Globals,
but as I’m not satisfied with that let’s go under
the hood of the Mental Ray settings...
Fig 11
We are selecting the miDefaultOptions node
(for example by typing “select miDefaultOptions”
in the MEL command line) (Fig10). This node
is basically responsible for the export of all
the settings to Mental Ray. The regular render
globals are practically a more user friendly
“front-end” to the miDefaultOptions. There’s
also some stuff in the mentalrayGlobals node,
but this does not affect us right now. As you can
see, the FG Diffuse Bounces attribute is actually
exposed; we set it to our desired depth, which is
2 for now.
It looks better (Fig11), but still appears to be
seriously under exposed. There are several
ways to adjust the general exposure level in
Fig 12
Mental Ray for Maya, but let’s choose the
easiest one: raising the Gain attribute of our
mia_exposure_simple...
You can navigate to the mia_exposure_simple
either by selecting your camera (to which it
is connected), or by opening the hypershade
and selecting it from the Utilities tab. I gave it a
serious punch and boosted the Gain up to 4.0
(Fig12).
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Environment Lighting
Twilight Chapter 02
Now it’s much better from an exposure point of
Fig 13
view (Fig. 13), but it looks very cold and not very
twilight-ish. You might want to experiment with
the sun’s direction, but if we overdo this then
we will lose the nice light which is playing on the
floor. I therefore decided to solve the problem
using the mia_physicalsky - the environment
shader which is responsible for pretty much the
entire lighting situation.
I upped the Haze parameter to 2.0, which gives
us a nice “equalization” of direct light coming
Fig 14
from the sun, and the light intensity of the sky
(Fig14). At lower haziness, the sunlight would be
too dominant for our twilight atmosphere. I then
shifted the Red/Blue attribute towards reddish,
to achieve a warmer look (if I wanted to shift
it towards blueish, i.e. doing a white balance
towards a cooler temperature, I would have to
use a negative value for the Red/Blue Shift).
I also slightly increased the Saturation, which
is pretty much self explanatory. Now, for an
interesting little trick to make the whole lighting
situation more sunset-like, whilst still maintaining
the direct light on the floor (i.e. the actual light
angle), I increased the Horizon Height to 0.5.
This not only shifts the horizon line but also
makes the whole sky system think that we have
Fig 15
a higher horizon, and thus provides a more
accentuated sunset situation. Remember this
does not have too much of an effect, yet it’s
still an interesting way to tune the general look.
The last two things I changed were the Horizon
Blur and the Sun Glow Intensity, however both
of these attributes don’t have much of a visible
effect on the general illumination of our interior.
Once we’re finished setting up the basic look,
we can go about configuring the Render Globals
for the final quality (Fig15). First of all, let’s
increase the Final Gathering quality, since we
can reuse the Final Gathering solution later
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Environment Lighting
Chapter 02 Twilight
Fig 16
on. In Fig15, you can see the values I used: 64
for Accuracy, which means each final gather
point shoots - in a random manner - 64 rays
above this point’s hemisphere (less accuracy
would give us a higher chance of a blotchy
Final Gathering solution). To work against the
blotchiness we could also increase the Point
Interpolation to really high values, like 100+,
but this would most likely wash out the whole
contrast and detail of our indirect illumination
if we don’t have a sufficient Point Density
value. The Point Density - in conjunction with
a reasonable Point Interpolation - is the most
responsible part in achieving nicely detailed
shadowing, and so we have to find a good
correlation between these two. In our case, I
Fig 17
found it sufficient to have a Point Density of
2.0 and a Point Interpolation of 50. You might
want to try a Density of 1.0 (or even 0.5) if
you think the former settings take too long
to calculate, but you’ll surely notice the lack
of detail in the indirect illumination. Note that
increasing/decreasing the Interpolation does
not affect the Final Gathering calculation time
at all. It also does not hurt the actual rendering
time too much. The crucial value is the Point
Density which adds to the calculation time, as
well as the accuracy. Also note that you might
be able to comfortably experiment with the Point
Interpolation if you freeze the Final Gathering
solution (set Rebuild to Freeze).
Fig 18
It looks much better now (Fig16), but there are
still some areas that seriously lack detail, such
as the door region. To reveal these details we
could render a simple Ambient Occlusion pass
and multiply it over in post production. This
would accentuate the problem areas, but at the
same time it would add this typically all-present,
physically incorrect and visually displeasing
ambience. To overcome this, and still use the
advantage of Ambient Occlusion, we can use
the mia_material’s internal Ambient Occlusion
mode...
We simply need to enable it in the shader, and
set the Detail attribute to On (which it is by
default) (Fig17). This special Ambient Occlusion
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Page 22
Environment Lighting
Twilight Chapter 02
mode is intended to enhance the problem areas’
Fig 19
details, where the Point Density might still not
suffice.
To enable the Ambient Occlusion in all shaders,
we simply select them all from the hypershade
and open the attribute spread sheet, from
Window > General Editors > Attribute Spread
Sheet (Fig17). There we navigate to the attribute
called Ao_on and set it’s value to 1 (On).
Although it still might be physically incorrect, it
reveals all the details that the Final Gathering
was not able to cover (Fig19). Of course, it still
looks very coarse, and this is mainly because
the general sampling settings are still at
extremely low values.
Fig 20
To ensure nice edge antialising, as well as
better shadows and glossy sampling, we set the
Min/Max Sample Levels to 0/2 and the Contrast
values both to 0.05 (Fig20). The filter should
be changed, too; I chose Mitchell for a nicely
sharp image. I’m also raising the Reflection
Gloss Samples (Refl_gloss_samples) up to 8
in the mia_materials. Note: this happens on a
per shader basis, and we can use the attribute
spread sheet again to do this all at once for all
shaders.
Last time we rendered to a full 32bit floating
point framebuffer. This time, for my final render,
I chose to render to a half 16bit floating point
framebuffer (Fig21). The half 16bit takes less
Fig 21
storage (and bandwith) but still provides the
increased dynamic range of floating point
buffers. If we want to render the floating point
buffer right out of the GUI, without batch
rendering, we need to make sure the data
written into the buffer actually is floating point;
thus the Preview Convert Tiles in the Preview
tab of the Render Globals needs to be switched
On, and the Preview Tonemap Tiles option
needs to be switched Off. This will produce
funky colours in your render view preview,
but the image written to disk (typically in your
project’s images\tmp folder) should be alright.
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Environment Lighting
Chapter 02 Twilight
Fig 22
The use of a half 16bit framebuffer forces us
to use ILM’s OpenEXR format, as it is the only
supported format right now for this particular
kind of framebuffer (Fig22). That’s not actually
bad, since OpenEXR is a very good and widely
used format, nowadays.
Fig 23
Here’s the final rendered, raw image (Fig23)
- a good base for the post production work. In
my final interpretation I decided to exaggerate
the colours that make a dramatic twilight
atmosphere. Again, there is no painting
happening, only colour enhancement which was
done using Adobe Lightroom 1.0 (Fig24).
Fig 24
I hope you have enjoyed following this second
part of the series as much as I have enjoyed
writing it. Stay tuned for part 3 where we will be
covering an extremely interesting - and no less
challenging - lighting situation: moonlight.
www.3dcreativemag.com
Page 24
Environment Lighting
Originally designed & modelled by:
Richard Tilbury
Tutorial by:
Florian Wild
For more from this artist visit:
http://individual.floze.de/
Or contact them:
mymail@floze.de
Chapter 03
Chapter 03
Natural Exterior Lighting
Moonlight
Moonlight
Moonlight Chapter 03
Natural Exterior Lighting
Fig 01
Moonlight
Hello and welcome to the third part of the
environment lighting series for Autodesk Maya
8.5, where we will be discussing a very interesting
lighting situation: natural moonlight. So let’s wait
for full moon and a cloudless sky, then we can turn
off the lights and get started...
1. If you followed the preceding two tutorials
(which I recommend), you will already be familiar
with the scene (download can be found at the end
of this tutorial; click on the Free Resources logo)
(Fig01).
Before we start placing lights and tuning
parameters, we should take some time to think
Fig 02
about what ‘moonlight’ actually is. If you are
not interested in this concept then you might
want to skip or come back later to the next two
paragraphs, as they are not essential. They are
however valuable for the understanding of why
certain methods have been used in the execution
of this moonlight setup.
So what is moonlight? First of all, by moonlight
we mean a nighttime situation, and for the sake
of convenience let’s say we have a full-moon/
nighttime situation. There are several sources
and components of illumination in this setting (i.e.
in the descending order of energy): the moon
itself (by scattering sunlight from its surface in all
directions), the sun (by scattering light around the
Fig 03
edge of the earth), planets and stars, zodiacal
light (dust particles in the solar system that scatter
sunlight), airglow (photochemical luminescence
from atoms and molecules in the ionosphere),
and diffuse galactic and cosmic light from galaxies
other than the milky way (source: A PhysicallyBased Night Sky Model). All of these illumination
sources have their characteristics, and in order to
super-realistically simulate such a night-sky, we
would have to account for all of them. But please
bear with me, we will only be concentrating on the
moon itself, and an atmospheric ‘soup’ including
all the other ingredients. Besides, and this is very
interesting, even if we did that super-realistic
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Environment Lighting
Chapter 03
Fig 04
Moonlight
night-sky simulation then we would perhaps get
a very photo-realistic rendering, but I am sure
many people would be disappointed by it. This is
for the simple fact that, seeing a night-sky/moonlit
photograph is fundamentally different from actually
viewing such a scene with our own eyes. The
photograph might be physically correct, but also
completely different from what we are used to
physiologically perceiving. In the end, we would
most likely shift the photograph’s white balance
towards blue, because this is what we are used
to seeing, which is opposed to how a camera
sensor works in dim lighting levels. The sensitivity
of the human perception of light is shifted towards
blue; the colour sensitive ‘cones’ in the eye’s
retina are mostly sensitive to yellow light, and the
Fig 05
more light sensitive ‘rods’ are most sensitive to
green/blueish light. At low light intensities, the rods
take over perception and eventually we become
almost completely colour blind in the dark, hence
it appears that the colours shift towards the rods’
top sensitivity: green and blue. This physiological
effect is called the “Purkinje” effect, and is the
reason why blue-tinted images give a better
feeling of night - even though it’s not correct from a
photographic point of view.
2. So we will rely on a hint of artistic freedom,
rather than strict photo-realism, for this tutorial.
To simulate the moon’s light I chose a simple
directional light with the rotation: X -47.0 Y -123.0
Z 0.0 (Fig02).
Fig 06
3. For the light colour I decided to use Mental
Ray’s mib_cie_d shader (Fig03). Its Temperature
attribute defaults to 6500 K (degree Kelvin),
which means an sRGB ‘white’ for this so-called
D65 standard illuminant, which is commonly
used for daylight illumination, will be as follows:
every temperature above 6500 K will appear
blueish, and every temperature below 6500 K
will appear reddish. The valid range is from 4000
K to 25000 K. Although the moon actually has a
colour temperature of around 4300 K, I chose a
temperature of 7500 K. This is not necessarily
correct from a physical point of view, for various
reasons.
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Environment Lighting
Moonlight Chapter 03
Firstly, the moon is not a black body radiator and
Fig 07
so its colour cannot precisely (only approximately)
be expressed with the Kelvin scale. Second,
the moon’s actual colour is mainly a result of
the sunlight (with a temperature of around 5700
K - still lower than the white point of our D65
illuminant, or in other words more reddish if
expressed with it), a slightly reddish albedo of
the moon’s surface and the reddening effect
of rayleigh scattering (blue light, i.e. smaller
wavelengths, tend to scatter more likely than
red light and greater wavelengths, therefore a
higher amount of blue light gets scattered in
the atmosphere leaving more red light from the
perspective here on Earth). This would, in photoreality, surprisingly yield a quite reddish moonlight,
even if we did choose a very low white balance
for our photograph at maybe around 3200 K
Fig 08
(which is considered ‘tungsten film’). However, for
the physiological reasons described previously,
I went for 7500 K on the D65 illuminant as this
gives a pleasing - not too saturated but still very
natural - blueish light. To cut a long story short,
if you wanted to go for photo-realism you would
have to use a reddish light source, but you would
most likely white balance everything towards blue
afterwards to achieve the cool night feeling! And
that’s basically what I did - only in a rush...
4. For the same reasons I chose a turquoise
(blue-greenish colour) for the surrounding
environment, which was simply applied as the
camera’s background colour (Fig04). Although
this will only have a subtle effect it makes sense
Fig 09
for the completeness, and after all we will see this
colour through our back windows. Note that what
we see on the actual Background Color’s colour
swatch will be (deliberately) gamma corrected
later on. To overcome this and to ensure that the
colour I choose is the colour that I will see later
on in the rendering, I use a simple gammaCorrect
node, with the inverse gamma applied. The
gammaCorrect is connected via mmb drag&drop
in the ‘Background Color’ slot.
5. Before we push the render button, let’s make
sure we have something that takes care of our
indirect illumination, and that we are rendering
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Page 29
Environment Lighting
Chapter 03
Fig 10
Moonlight
in an appropriate colour space. For the sake of
simplicity I chose final gathering with Secondary
Diffuse Bounces for the indirect light contribution
(Fig05). This is easy to set up, yet effective. As
you can see I set low quality values, but since we
are only doing a preview this will suffice.
6. Because there is a little shortcoming with the
Secondary Diffuse Bounces setting, I’m selecting
the miDefaultOptions node (Fig06), which is
basically the back-end of the render globals. There
I set the FG Diffuse Bounces to 2, which is my
desired value for the indirect illumination bounces.
To select the miDefaultOptions simply type “select
miDefaultOptions” (without the quote marks), in
the MEL command line, and then hit Enter.
Fig 11
7. I’m also setting the Ray Tracing depths to
reasonable values - they seem very low, but are
absolutely sufficient for our needs (Fig07).
8. To take care of the desired colour space
(sRGB) we simply need to set a gamma curve in
the Primary Framebuffer tab of the render globals
(Fig08). Since a gamma curve of 2.2 is similar to
the actual sRGB definition, we only need to set the
Gamma attribute to 1/2.2 = 0.455, as this is how
Mental Ray’s gamma mechanism works. For a
basic understanding as to why we should render in
sRGB, I greatly encourage you to go through the
Note on Colour Space in the first tutorial of this
series (July 2007 issue), if you haven’t already.
Fig 12
As a general note, it is to do with the non-linearity
of human light perception and rendering in a true
linear space (gamma = 1.0), as any renderer
usually does by default, which is the main reason
for CG looking “CG-ish”. (Spread this knowledge
to your buddies and with this understanding you’ll
be the cool dude at every party, trust me!)
9. So here is our first test render (Fig09). It looks
a bit dark, and since we want to have a full-moon
the shadow seems a bit too sharp.
10. To soften the shadow, let’s increase the Light
Angle of our directional light (Fig10). Because
widening the light angle introduces artifacts, we
should also increase the amount of shadow rays
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Page 30
Environment Lighting
Moonlight Chapter 03
to yield a smooth and pleasing shadow. I’m also
Fig 13
increasing the intensity of the mib_cie_d a little.
11. This is a good base (Fig11) and all we need to
do now is increase the general quality settings for
our final render.
12. For better anti-aliasing and smoother glossy
reflections we should crank up the global sampling
rates (Fig12). A min/max value of 0/2 and a
contrast threshold of 0.05 should suffice. I used a
Gauss 2.0/2.0 filter for a sharp image.
13. For the final gathering this time I chose a fairly
unorthodox method... Remember the last couple
of times we used the automatic mode, which
in most cases does a really good job? Well, in
automatic mode all we need to worry about are
Fig 14
the Point Density and Point Interpolation values.
However, sometimes in this mode the interpolation
becomes quite obvious and displeasing, especially
in corners where you can usually spot a darker line
where the interpolation happens to be very dull.
For a sharper interpolation, I decided to use
the scene unit dependant Radius Quality
Control (Fig13). It generally takes a little time to
estimate the proper min/max values (in scene
unit values), but as a guideline you might want
to do a diagnostic automatic Final Gathering
solution (see Diagnostics in the render globals)
as a base, to see its point densities. Then, step
by step, approximate this density with the scene
unit Max Radius control. Note that the density is
Fig 15
only decided by the Max Radius (the lower the
Max Radius, the more Final Gathering points are
being generated); the Min Radius only decides for
certain interpolation extents.
Once you are satisfied with this general density,
you will usually want to raise the Point Density
value. This Point Density is added to the density
we estimated with the min/max radii; however,
the interpolation extents do not change so we are
basically only adding points to the interpolation,
which is similar to raising the Point Interpolation in
automatic mode (only more rigid and somehow it
puts the cart before the horse this way).
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Environment Lighting
Chapter 03
Moonlight
It’s always good to know how and why things are
happening, and this knowledge is useful if you
ever want to use the Optimize for Animations
feature. It’s also a bit easier if the View radii are
being used, since the min and max radii can be
generalised (25/25 or 15/15 in pixel units is a good
starting point).
14. As a little trick to enhance details in our
scene, I turned the Ambient Occlusion on in the
mia_material shaders, in the Details mode. Simply
select them all and switch the Ao_on attribute to 1
(On), using the attribute spread sheet (Fig14). The
Details flag, in combination with Final Gathering,
ensures that we don’t get that rather unpleasant
dark-cornered-and-strange Ambient Occlusion.
15. To prepare for the final render, I set the
framebuffer to half floating point and the image
format to OpenEXR (Fig15). Floating point means
the image gets stored with a high dynamic range,
as opposed to 8bit or 16bit integer images, which
are clipped at RGB values greater than 1.0
(‘white’). With a floating point image we can map
values greater than 1.0 back to the visible range
in post-production (i.e. we will be able to eliminate
completely burnt areas).
Half floating point means the floating point with
half precision, taking less memory and bandwidth.
To be able to render a floating point image
right out of the GUI we need to set the Preview
Tonemap Tiles to Off, but keep the Preview
Convert Tiles: On. The preview in the render view
might look very dark and psychedelic, but the
OpenEXR image written to disk in the images\
tmp folder will be alright, and that’s the one we will
be processing later on in Photoshop (or any other
HDRI editor of your choice).
16. Here’s my final render without post processing
(Fig16).
17. As with any photograph we shouldn’t judge the
raw shot; instead let’s take it into the ‘darkroom’
and apply some colour and contrast improvements
here and there (Fig17).
www.3dcreativemag.com
Page 32
Environment Lighting
I hope you’ve enjoyed following this little exercise
as much as I have enjoyed writing it! Sadly this is
the last part concerning natural exterior lighting,
but the upcoming electric light tutorial will be no
less challenging and just as much fun, I’m sure!
Originally designed & modelled by:
Richard Tilbury
Tutorial by:
Florian Wild
For more from this artist, contact them:
mymail@floze.de
Chapter 04 Electrical
Chapter 04
Artificial Interior Lighting
Electrical
Electrical Chapter 04
Environmental Lighting
Electrical
Hello and welcome aboard! This time, following on from our last tutorial
on natural moonlight, we’ll be discussing a very “CGI-traditional” style of
illumination: electrical lighting. Although this kind of light is considered
artificial, we will learn later on that it has a very natural background (at
least as long as we stay with a tungsten light, which we propose to do so
in this tutorial).
So why “CGI-traditional”, you ask? Well, ever since there was CGI
(Computer Generated Imaging), tungsten bulbs have been very easy
to simulate, for mathematical reasons. The classic tungsten bulb has a
relatively limited area of light emission, which in the 3D/simulation world
can be simplified down to a infinitely small point: the classic point light (as
a side note, its little brother, the spot light, is nothing but a point light but
with more sophisticated features). In the history of CGI, this infinitely small
point made it possible to render 3D images quickly and effectively, due
to logic reasoning. In order to simulate a light source, we basically need
three points for the maths; i.e. the position of the eye of the observer,
since the point is strictly determined. Back in the times when computers
the point on the surface that’s being lit (called the “intersection point”),
weren’t as “high-clocked” as they are today, this was crucial, and point
and the position of the light source. All of these together mathematically
light based lighting was mandatory, along with closely related techniques
make out the rendering, and since an infinitely small point is obviously
such as spotlights and directional lights (which use an infinitely far away
the most simple element in 3D space, it can be computed with very little
point, instead). So for CGI, the Point light is pretty much as important as
expense in this context. Even more importantly, it becomes “noise-free”,
Edison’s light bulb is for real life. Computer light sources have evolved
since then, however; just as the real light bulb has. For both, the principles
have also stayed the same. And still, the most believable deployment of a
point light is at the simulation of a tungsten bulb.
Now with the history covered, let’s have a closer look at how tungsten
bulbs actually work, and why they look as they do. This is, as always,
the essential starting point when trying to simulate a specific subject.
The operation of a usual incandescent bulb is quite simple: an electric
current is passed through a tungsten (also called wolfram) filament,
which is enclosed by a glass bulb that contains a low pressure inert gas,
to avoid oxidation of the electrically heated filament. Depending on the
type of the filament, the operation heat is typically between 2000 and
3300 degree Kelvin (around 3140 to 5480 degree Fahrenheit, or 1727
to 3027 degree Celsius). This thermal increase induces radiation (also,
but not only) in the human visible light spectrum, in the form of a socalled “black body”. The interesting thing about this black body (which
actually is an idealised physical model of a radiator/light emitting body)
is that its emitted spectrum, i.e. the colour, can be estimated by solely
knowing the (absolute) temperature of the black body, according to
Planck’s Law. On the contrary, one application of this is in astrophysics,
where scientists can measure the temperature of a star by analysing its
spectrum. And furthermore, this way the movement of stars and galaxies
www.3dcreativemag.com
Page 35
Environment Lighting
Chapter 04 Electrical
can be determined, if this estimated spectrum
Fig 01
is shifted either towards blue (getting closer) or
red (moving away), due to the electromagnetic
equivalent of the sonic Doppler effect, called
“redshift” or the “Hubble effect”.
Well, this all means we have (at least in theory)
a strictly defined spectrum, or colour in our
case, for a glowing tungsten bulb. This colour
lies on the so-called “Planckian locus” (Fig01);
a coordinate in a particular colour space, which
ranges (for our needs) from the visible red, over
white, to blue. There are several “black-bodyKelvin-temperature-to-colour” converters on the
Internet, but fortunately there is a standard tool
that ships with Mental Ray, which makes our life
a little easier!
Fig 02
It’s called, guess what, “Mib_blackbody”, and
can be found in Maya under the MentalRay
Lights tab in the Hypershade menu (Fig02). This
utility outputs the desired colour, according to
the temperature we feed it.
So let’s model the actual light. To deliberately
break tradition, I decided to use a spherical
Fig 03
Area light (instead of the good ol’ Point light)
which I placed close to the centre of the actual
bulb’s geometry, so that it’s encompassed by it
(Fig03). Obviously, if we rendered it this way, we
would face trouble due to the occlusion caused
by the bulb’s geometry.
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Page 36
Environment Lighting
Electrical Chapter 04
Fig 04
There are several ways to get around this. We
can either adjust the bulb’s glass shader so
that it handles the transparency (although we’ll
have to increase the ray depths accordingly).
Or, and this a little smarter in this case, because
we won’t have to mess with the ray depths, we
can simply exclude the bulb from shadow and
reflection/refraction tracing by setting some flags
in the object’s Shape node (Fig04). Since the
bulb is incandescent anyway, we can neglect its
shadow.
Fig 05
To give our light the desired colour, I simply
create the mib_blackbody node and connect it
to the Area light’s colour slot (Fig05).
Fig 06
I also set its decay rate to Quadratic, which
is very important in order to give it a natural
falloff and to obey physical laws. The intensity
is left at 1.0; I completely hand this over to the
mib_blackbody, where I also set a reasonable
temperature for our tungsten filament
(something between 2000 and 3300 - I decided
for 3000 degree Kelvin) (Fig06). I repeat all
these steps for the second bulb, except that I
use the same mib_blackbody node for its colour,
just to speed up the workflow a little as we can
assume that both bulbs are of the same type.
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Page 37
Environment Lighting
Chapter 04 Electrical
We’re pretty much ready to render now. Before
Fig 07
we push the button though, let’s adjust the
Render Globals to something more reasonable.
The Ray Tracing depths for example are not
quite what we need, although they only need
changing slightly (Fig07).
I’m also switching on Final Gathering for the
indirect light contribution. I set the Accuracy,
Fig 08
Point Density and Trace Depths to a “good-toplay-with” value; we can change these for the
final render of course, later on (Fig08).
Because the FG Diffuse Bounces setting
has a little shortcoming in Maya 8.5, I set
Fig 09
them in the actual controlling node, which
is called “miDefaultOptions” (type “select
miDefaultOptions”, without the quote marks,
into the MEL command line to bring it up in the
attribute editor) (Fig09).
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Page 38
Environment Lighting
Electrical Chapter 04
Fig 10
Lastly, but most importantly, we have to get
into the right colour space, which is sRGB
- the commonly used space for things like
photographs. Although we cannot precisely
apply this colour profile right away (at least not
easily in Mental Ray for Maya 8.5), we simply
apply a so-called “gamma correction curve” to
our image, with a value of value 2.2, which is
usually sufficient. This implies some caution;
because the textures we usually use are already
in sRGB, hence they are gamma corrected,
we need to “un-gamma” them before we
correct the whole image again. This may seem
awkward and unnecessary, but it makes total
sense for one reason: if we want the (gamma
corrected/sRGB) texture to look like what we
Fig 11
are used to it looking like, we need to remove
the gamma correction first, before we re-apply
it to the whole image. This may seem odd, but
it will make our picture look much more natural.
Thankfully, Mental Ray has this “removetexture-gamma-and-re-apply-it” thing built in
already, so we simply set the desired gamma
correction value in the Framebuffer > Primary
Framebuffer tab of the Render Globals (Fig10).
However, Mental Ray wants us to actually
specify the inverted function, which is 1/2.2,
equal to 0.455 in our case. For more information
on the gamma issue, I encourage you to read
the ‘Note on Colour Space’ in the very first part
of this tutorial series.
Fig 12
Well, here’s our first test render with the settings
above (Fig11).
Strange things are happening, I know. The
reason for this is the very close proximity of
geometry to our Area light. The Final Gathering
usually goes nuts on this! There’s an easy
solution: we simply set the Final Gathering
filter to greater than 0. I decided to use 1 as
this usually does a good enough job (Fig12).
Usually, it is desirable to completely avoid this
filter (i.e. leave it at 0), because it introduces
some strange bias in certain situations; for
example, if we had lit our scene completely by
HDRIs. So use it wisely, or only if you are forced
to, like in our case. If you are still encountering
www.3dcreativemag.com
Page 39
Environment Lighting
Chapter 04 Electrical
artifacts, try excluding the lamp guard and base
Fig 13
from the reflection/refraction tracing, as well.
Let’s see if it helped (Fig13) ... Yep, that looks
much better now! I’m preparing for the final
render now, by upping the general anti aliasing
quality.
The Final Gathering needs increasing, too
(Fig14).
And there we go (Fig15).
www.3dcreativemag.com
Fig 14
Fig 15
Page 40
Environment Lighting
Electrical Chapter 04
Fig 16
The last thing I added was the mia_material’s
built-in detail ambient occlusion, by selecting
all the mia_materials and changing the Ao_on
attribute to 1 (on) in the attribute spread sheet
(Fig16). This reveals small details without
hammering the well-known - and usually way
too strong - “ambient occlusion corner darkness”
onto our image.
Fig 17
Also, I decided to render to a more reliable,
fancy, super-duper 32bit framebuffer - simply
because everyone does! Seriously though, for
stills it’s better of course to render to a floating
point format. After all this, we’ll achieve a much
more peaceful sleep whilst the renderer works
overnight. However, for efficiency, I decided on
a 16bit half framebuffer, which is still a floating
point format but uses less space and bandwith.
To use this, the only possible file format for now
is OpenEXR, which is not a bad thing since
OpenEXR is quite fancy, really (Fig17).
Fig 18
After touching up the contrast and some of the
colours here and there, I came up with my final
interpretation (Fig18).
I hope you’ve enjoyed following this little tutorial
about electrical light, and I hope you’ll stay with
us for the next tutorial part, on candle light!
www.3dcreativemag.com
Page 41
Environment Lighting
Originally designed & modelled by:
Richard Tilbury
Tutorial by:
Florian Wilde
For more from this artist, contact them:
http://individual.floze.de/
Or contact:
mymail@floze.de
Chapter 05 Candlelight
Chapter 05
Artificial Interior Lighting
Candlelight
Candlelight Chapter 05
Artificial Interior Lighting
Fig 01
Candlelight
Ahoy, and welcome back to the fifth part of
our lighting tutorial series! Interestingly the
general matter on this one will technically be
the same as the last time, where we discussed
the behavior of electric light bulbs, however the
result will be considerably different. So lets turn
off the lamps and fetch the matches, to get our
candle light tutorial started.
In the last tutorial we already learnt the technical
aspects of heated bodies, like tungsten filament,
or wick. It became clear that in a simplified yet
meaningful way the emitted color always has
a very determined type, only depending on the
Fig 02
temperature of the heated body. And curiously
this special rule does not depend at all on the
material of the heated body. So we can pick up
where we left, and simply translate these rules
to our new topic.
Lets recall the behaviour of a heated ‘black
body’. Whenever matter is heated, it emits
photons with certain intensities at distinct
frequencies. This ‘fingerprint’ of the radiation is
then called a spectrum. Now a black body is an
‘ideal physical model’ which absorbs all radiation
and which does not reflect any at all. The
interesting thing about this is that the spectrum
(‘color’) of such a body is strictly defined by
physical law, and is solely dependant on the
Fig 03
actual temperature of the body. Of course this
is somewhat simplified, as the actual emission
spectrum of our heated material (i.e. carbon
and hydrogen, bound in the, say, paraffin of
our candle) is neglected this way. Still this
‘ideal model’ does a good job at simluating our
situation.
01. Now that we have an idea of how to model
the color of our candle-light we can start to give
it shape. According to gravity and buoyancy
laws (hot things move upwards due to their
lower density), the candle flame has this well
known ‘drop shape’. If you ever wondered how
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Environment Lighting
Chapter 05 Candlelight
Fig 04
a candle burns at zero gravity, see the right
side of Fig01 - the hot and ‘lighter’ gas does
not circulate (‘convect’) as well as down here
on earth, instead it spreads uniformly and no
oxygen (although available!) raises it, so it is
likely forced to become extinguished.
02. For the sake of simplicity I decided to use
a simple photograph of a candle flame as a
so called sprite, or billboard object (Fig02).
I already adapted the image’s hue to the
temperature we will be using later on, which you
might want to consider too, but more on this
shortly.
03. The billboard is then placed closely to
Fig 05
the wick (Fig03), to model the flame. This is
a simple and popular method of representing
a rather complex shape, be it flames, snow,
leaves, grass, pylons, and probably an arbitrarily
huge bunch of other things one could think of.
04. It obviously makes sense to take care of
certain factors when dealing with such ‘tricks’,
so I adjusted all necessary render flags of
this sprite, to avoid render artifacts (Fig04).
For example, it does not make sense to let
this helper object cast shadows (after all it is
replacing a light emitting entity), or to leave it
visible to reflections or refractions (the actual
light will handle this later on with the ‘highlights’).
Fig 06
05. The next rational step in our abstraction
of the candle light is to build the actual light
emitting 3d representative. I chose a spherical
area light for this job, with a little scale in the ‘up’
direction’ (Fig05). I placed it closely to where our
‘fake’ flame is, right above the wick. Since we
took care of the sprite’s render flags it does not
interfere with the light at all.
Now that we have our light source constructed,
we shall give it life with an appropriate color. As
described earlier, we have robust guidelines on
how to deal with this, in order to create naturally
looking candle light. We simply need to know
the approximate temperature at which a candle
flame burns on average. The sources on this
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Environment Lighting
Candlelight Chapter 05
however seem to diverge quite a bit; some state
Fig 07
a temperature of around 1300 Kelvin (~1000
degree Celsius, or ~1800 degree Fahrenheit)
and some even state it at around 2300 K (~2000
°C, or ~3600 °F). I went for the middle of these
values, and decided for a temperature of 1800
K, which equals to around ~1500 °C or 2800 °F.
This is the tempereatre (color) we should align
our candle sprite texture to, in order to yield a
convincing congruence in the rendering.
06. There are many Kelvin-to-color converters
on the internet which we could use to obtain the
desired color, but luckily there is also a built-in
tool that ships with mental ray for Maya. It is
called mib_blackbody and can be found under
the mental ray lights tab of the ‘Create Render
Node’ menu in the hypershade (Fig06).
Fig 08
07. This node only has two attributes we
need; the temperature (in Kelvin, or ‘absolute’
temperature), and an intensity value (Fig07). If
we wanted to really (really!) exactly simulate a
candle light, or any light at all, we would have
to actually know it’s luminous power, also called
luminous flux or lumen (read on this link for
further information: http://mentalraytips.blogspot.
com/search/label/photometry), and then we
would have to convert this value into the
Maya/mental ray world with some effort on both
the emitting (light) and receiving (camera) side.
Maya 2008 has some built-in improvements
on this, however, since we don’t do a radio/photometric scientific simulation we simply
Fig 09
GUESSTIMATE the intensity. I went for a value
of 2500. To finally make use of this little tool,
I connect it to the light’s color slot - the light’s
intensity is left at 1.0 (this is handled by the
mib_blackbody), and I also make sure the decay
rate is set to ‘Quadratic’.
That’s pretty much it for the scene part, lets
head over to the rendering department.
08. We prepare the final gathering settings for
quick yet meaningful convergence of the indirect
illumination (Fig08). We only need a few rays
(32) and a coarse point density (0.5) for our
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Chapter 05 Candlelight
Fig 10
preview. Of course we will refine everything for
our final image. I left the final gather ‘mode’ at
automatic, i.e. the ‘Optimize for Animations’ and
‘Use Radius Quality Control’ are kept OFF.
09. The trace depths however need to be
increased, along with the general raytracing
settings; I decided for 2 ‘bounces’, for the
diffuse contribution, which I revise in the
miDefaultOptions node (Fig09): although I turn
them ON in the render globals, they are stuck at
1 bounce due to a little bug. I want them to be of
depth 2, so I adjust them ‘under the hood’ in the
miDefaultOptions.
Before we actually render, we must take care
Fig 11
over the color space, so its time for our little
gamma-mantra (since we dont want odd and
cg-ish looking, grungy true-linear shadings).
Thus we put ourselves into the right color space,
which is sRGB, the commonly used space for
things like photographs. Although we cannot
precisely apply this color profile right away (at
least not easily in mental ray for Maya 8.5),
we simply apply a so called gamma correction
curve with a value of 2.2 to our image, which
usually is sufficient. This implies some caution:
because the textures we usually use are already
in sRGB, or hence gamma corrected, we need
to un-gamma them before we correct the
whole image again. This seems awkward and
unnecessary but makes total sense for a reason
Fig 12
- if we want the (gamma corrected/sRGB)
texture to look like we are used it to looking,
we need to remove the gamma correction first,
before we RE-apply it on the whole image. Odd
notion, but makes our picture look pretty and
more natural.
10. Thankfully mental ray has this removetexture-gamma-and-re-apply-it thing built in
already, and we simply set the desired gamma
correction value in the frame buffer>primary
framebuffer tab of the render globals (Fig10).
However, mental ray wants us to actually
specify the inverted function, which is
1/2.2=0.455 in our case. For more information
on the gamma issue, I encourage you to read
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Environment Lighting
Candlelight Chapter 05
the ‘Note on Color Space’ in the very first part of
Fig 13
this tutorial series.
11. A quick test render yields some strange,
blotchy artifacts though (Fig11). This is due to
the close proximity of certain objects to the area
light - we would have to either move them (or
the light) a little farther away, or exclude them
from the final gathering and reflection/refraction
computation somehow. Since we obviously have
a great demand to keep the light close to the
candle, we are forced to take the latter solution.
12. We simply switch OFF the corresponding
render flags in the candle’s and wick’s shape
node (Fig12). This basically cures the brightblotches-problem. To furthermore suppress
these kinds of blotches, I decided to use a final
Fig 14
gathering filter of 1. This filter should be handled
with care, and only be used as a last resort.
13. Another test rendering verifies this (Fig13),
and we have take off clearance. Lets raise
the quality to something more usable (which
basically means we are extending the flaps, to
continue the metaphor).
14 . First, lets raise the general sampling
settings (Fig14). The minimum level is kept at
0, the maximum level is set to 2, which means
a maximum of 4^2, or 16 samples per pixel
(whereas the rule is 4^n, and n means the
sampling level). The contrast is lowered to 0.05
each. I usually use a narrowed gauss filter of
Fig 15
width 2.0 (default is 3.0!) both in x and y, which
gives sharp, fast and nice sample filtering.
15. In the end, lets give the final gathering a final
quality (Fig15). I increased the rays (accuracy)
to 64, and the point density to 2.0, which should
be more than enough for our still image.
16. I also turned on the ‘detail ambient
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Environment Lighting
Chapter 05 Candlelight
Fig 16
occlusion’ mode of the mia shaders. All you
need to do is to select all the mia shaders in the
hypershade, open up the attribute spread sheet,
and set the Ao_on attriubte to 1 (ON) (Fig16).
This ensures we see all the little details that are
too small to be captured properly by a rather
coarse final gathering solution.
17. Last but not least, we could go for a floating
Fig 17
point framebuffer, if we liked. To do so from
within the render view and without going to a
batch, we simply had to switch the framebuffer
to either RGBA (Float), or RGBA (Half), turn
the ‘Preview Convert Tiles’ ON, the ‘Preview
Tonemap Tiles’ OFF, and use an appropriate file
format, like OpenEXR (Fig17).
18. Thats it. I came up with this final
Fig 18
interpretation, after going through a few color,
white-balance and contrast image operations
(Fig18).
I hope you enjoyed following our little candle
light exercise as much as I enjoyed writing it! I’d
be glad to welcome you next time to our final
part, which is probably the most challenging
and most definitely the eeriest one: about
underwater lighting!
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Environment Lighting
Originally designed & modelled by:
Richard Tilbury
Tutorial by:
Florian Wild
For more from this artist, contact them:
http://individual.floze.de/
Or contact:
mymail@floze.de
Chapter 06 Underwater
Chapter 06
Artificial Interior Lighting
Underwater
Underwater Chapter 06
Artificial Interior Lighting
Underwater
Hello and welcome to the sixth and last part of
our environment lighting tutorial series! In the
preceeding parts we discovered the world of
natural environmental lighting, artificial kinds
of lighting, and a combination of the two. In
our last feature we will be discussing a rather
special case: that of an underwater scenario.
This implies some more or less ‘unusual’
pre-requisite. More precisely, we will be in
need of a truely visible ‘medium’, let’s call it
volume or ether. Most often people tend to
fake such volume by simply using so called
‘volume shadows’ on their 3d lights, i.e. lights
casting a visible ‘light ray’ into an apparent
(though not existant) volume. This is not the
real deal, however it is a favored method of
both professionals (because it renders fast,
which is essential specially for animations) and
beginners (because its rather easy to set up
and.. well I dont know. But its like the No.1 thing
people wish to do when getting their hands on a
3d program). Anyhow, we will be going the way
of the cowboy, or cowgal, and do it the tough
style. Since this is all about rendering stills, we
can afford to have this extra nuance of ‘bought’
prettiness.
Well. So we’re back aboard.. though this might
be a rather inappropriate description - we are
sunk! The ship’s body is below the waterline and
filled with seawater. To believably illustrate this
situation shall be the challenge of our tutorial.
We will also be creating an eerie, or unfamiliar,
uncommon lighting to support the feeling of
being in a different world.
Before we start to do anything we need to have
a few thoughts on this different world, because
this time we actually have a whole different (or
lets say: a more exaggerated) situation than
usual. Mainly there are two things we need to
consider: First WHAT makes underwater look
underwater, and second HOW can we achieve/
simulate it. This might sound trivial, and in fact
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Environment Lighting
Chapter 06 Underwater
the circumstances are so trivial indeed, that
most people seem to forget about them.
1. Lets begin by comparing our usual situation
(land / more or less dry air) with our new
situation (under the sea). In our habitual
environment, like our office, the living room,
or wherever inside a building, we usually do
not have much of a visible ‘volume’ - except if
we romp around and raise some dust. When
this dust gets into the air, it naturally, like any
matter, reflects light. Thus it gets ‘visible’. The
more dust we raise into the air, the ‘thicker’ the
apparent volume gets, and the light rays seem
to become actually visible - although all we see
is the dust reflecting them. There is a nice (albeit
philosophical) quote of Andre Gilde that aptly
says: “Without the dust, in which it flashes up,
the sunray would not be visible”.
Now there are more ‘things’ than plain dust
in the air we breath, in fact there are tons
of gases and particles which all make up
what is commonly called the ‘aerosol’. This
rather invisible mixture of microscopic solid
particles and liquid droplets have the same
scattering impact on incident light as the regular
(substantially larger) airborne dust.
This has an interesting effect: when light gets
scattered (i.e. forced to diffusely deviate it’s
naturally straight trajectory) by a surface much
smaller than the wavelength of it (like the
aerosol ingredients), the so called ‘Rayleigh
scattering’ occurs. Named after the physicist
Lord Rayleigh, this general approximation rule
says that the scattering ‘probability’ of a light
ray is dependant on its wavelength - whereas
the smaller wavelengths (blueish, ultra violet
domain) have a higher chance of getting
scattered than the larger wavelenghts (reddish,
infrared domain) (Fig01). Have you ever asked
yourself why the sky is blue? THIS is the
answer. The rather neutral, virgin and ‘white’
sunlight enters the earth’s atmosphere, and the
distinct portions of it get scattered by the aerosol
- since the blue part of the light has a largely
higher probability to get scattered, we seem to
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Underwater Chapter 06
be surrounded by a diffuse blue environment.
As opposed to a sunset or dawn, where mostly
unscattered light from the direction of the sun
reaches the observer - and appears red, due to
the lower wavelength.
Fair enough. Much pondering about the air, but
what about our concrete underwater situation?
Well, its basically the same story! The ocean IS
blue. Not only because it reflects the sky, but
also because of the Rayleigh rules explained
above. This scattering rules basically apply to
anything at anytime. In cgi we only neglect it, or
often we fake it based on observational facts.
And after all, computing true wavelength based
Rayleigh scattering is a seriously complex task,
and its questionable if the effort can be justified,
since it’s mostly rather marginal effect would
‘steal’ the rendering time we could spend on
other things that make our image pretty.
Have you ever asked yourself for example: why
do Maxwell Renders of outdoor images look
faint, whilst the indoors look pimp? Because
they neglect this light scattering (at least to
this point in time)! The scattering effect is not
as apparent in the indoor/interior renderings,
but has a large impact on the ‘naturalness’ of
outdoor, larger scale situations. The Rayleigh
rule is omnipresent, unless you’re in a complete
vacuum.
And it is even more evident in ‘thicker’ mediums,
or volumes, like the ocean water, which is
full of more or less tiny particles. The only
difference here is that the light gets scattered
and absorbed earlier, which is often referred to
as a higher ‘extinction’. A light ray entering such
volume has a certain probability to either get
scattered forwards (along it’s original trajectory),
backwards (the direction it came from),
something inbetween, or to get completely
absorbed by some particle. Every volume has
it’s own characteristics at how much of each of
the former criteria is being applied, not to forget
that the wavelength of the light ray looms largely
over this...
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Chapter 06 Underwater
Fig 01
This behavior can be modelled, or simulated
by a so called ray marching shader. We are not
going to obey the wavelength dependant rules
strictly (it’ll be more of a guesstimation), but lets
finally get our hands on our actual scenery.
As a reference I like to use http://www.
underwatersculpture.com/ by Jason Taylor,
which has various and no less beautiful
photographs on the day-to-day-thingsunderwater subject.
Fig 02
2. To build up our medium, I decided to simply
create a large surrounding cube (Fig02) as a
‘container’ of our volume. This is the simplest
and mostly fail-safe way to set up this kind of
stuff. We could alternatively build our volume
through our camera’s volume shader slot,
which would basically have the same effect
unless a ray would hit ‘nothing’, where this
second approach would simply return the
un-approximated environment color. This
alternative method could take longer to render,
because the ray marcher could possibly take
some more and unncessary steps further into
the depth (not in our case however).
The ray marching utility we will be using is the
Fig 03
rather ancient, though still nicely working mental
ray ‘parti_volume’ shader, which can be found
under the ‘mental ray Volumetric Materials’ tab
in the hypershade. This is not to be confused
with the parti_volume_photon, which is used
for volume photon tracing, but we will not use
photons to obtain indirect illumination in our
tutorial anyway. Our method will be a bit less
accurate but still nice and fast enough to create
our desired look and feel.
3. Lets have a look at the volume shader.
Foremost, we assign a new ‘black’ surface
shader to our cube container, and connect the
parti_volume to its shading group’s ‘Volume
Shader’ slot (Fig03). Thats pretty much it for the
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Underwater Chapter 06
set-up part, and we can have a closer look at
Fig 04
the parti_volume’s diverse attributes.
4. Most important for our needs right now is
the scattering part (Scatter, Extinction), the so
called scatter lobes (R, G1, G2, more on this
later), and the ray marching quality settings
(Min_-, Max_step_len). The other attributes,
which we will neglect however, are for filling the
volume only partially (Mode - 1 means ‘do it’
- and Height), to add a noise, or rather density
variation (Nonuniform, 0.0 means ‘no noise’)
and stuff we really dont need (Light_dist, Min_
level, No_globil_where_direct). As you can see,
there’s lots of techy stuff, but we’ll concentrate
on the essential things. (Fig04).
First the scattering factors, Scatter and
Fig 05
Extinction. Scatter basically controls the color
of the medium and is closely related to the
Extinction, which controls the density of the
medium. Both go hand in hand, and the hassle
about this is that to work with half-way rational
values we need to have a quite dark Scatter
color and a quite low Extinction factor - if any of
the two goes into higher extremes we’ll typically
end up with undesired results. So I decided for a
value of RGB 0.035, 0.082, 0.133 for the Scatter
color, which is a natural blueish tint. Since we
don’t do wavelength dependant calculations I
decided for this predominant color that mimics
and supports the Rayleigh rules explained
above. For the Extinction I used a low appearing
value of 0.004, but keep in mind that this is
Fig 06
all correlative with the Scatter color, and very
sensitive. So this value will give us an extinction
that swallows almost all of the light in the rear
corners, and that’s way enough.
Now about the scattering lobe. That’s a bit
more difficult at first glance. Basically, a
negative value for G (either G1 or G2) means a
backscattering lobe (back into the direction the
light ray came from) and a positive value means
a forward scattering lobe (forward along the
original trajectory of the light ray) - and R simply
means the mixture between G1 and G2. So you
typically chose one backward scattering lobe
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Chapter 06 Underwater
Fig 07
(i.e. a negative value for G1) and one forward
scattering lobe (i.e. a positive value for G2), and
weighten both with the R attribute. Whereas 1.0
for R means ‘use only G1’ and 0.0 means ‘use
only G2’ and 0.5 would weight both equally... I
know - there must have been some really funny
guy at mental images who wrote this shader,
and I’m pretty sure he’s still laughing up his
sleeve.
Anyhow. I chose a rather foward scattering
volume, but I encourage you to experiment with
the values. The forwardish scattering creates
these nice glow-like appearing light sources
when the light points towards the camera (its
vice versa if the light is e.g. behind the camera
Fig 08
of course). So I used R 0.1, G1 -0.65, G2 0.95
for my final image.
Last but not least I trimmed the Min_- and
Max_step_len to 50.0 each. This attribute
decides at which distances (step lengths) to stop
for looking up a volume sample - hence the rays
‘march’ through the medium, and the lower the
step lengths the more samples will be taken, the
better (less noisier) the image quality gets and
the longer it’ll take to render. If you think it takes
too long to render, boost this value up. On the
other hand, if you think you get too much noise
and artifacts in your image, reduce it. Generally
however the manual proposes to use a value of
about 10 percent of the Max_step_len for the
Fig 09
Min_step_len, so you might want to try this as
well (5.0min/50.0max). It is worth mentioning
that the step length values are in actual scene
units, so in our case it looks up a volume sample
every 50 centimeters.
5. Ok, we have our medium set up and running
(almost), now lets create some lights to make it
shine. Since our volume shader relies more on
direct rather than indirect light we cannot rely
much on the later final gathering for the ‘diffuse’
incoming illumination. That’s why I created two
area lights for this job, one above the hatch,
and one right behind the rear windows. For the
main light source however I used two spot lights
shining in from outside (Fig05).
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6. For these main lights I used a mib_blackbody
Fig 10
helper utility at 2200 Kelvin to obtain a rather
warm and diver-flash-light-like color (Fig06)
(the method of using a blackbody temperature
as color source has been explained more
extensively in the two preceeding tutorials!).
Though one could also imagine that its the sun
shining in from windows, you must decide this
and play around with it (in the words of Bob
Ross: there’s no failures, only happy accidents!).
7. The two area lights need a mixture of natural
blue (due to Lord Rayleigh’s stuff) and green
(due to many small greenish micro organisms
floating in the sea, like plankton or algae).
This mixture is commonly referred to as cyan,
turquoise, mint or cobalt, depending on which
color is weighted, or most felicitous: aquamarine
Fig 11
(Fig07).
8. So far so good? Uhm.. there’s one last very
important thing we need to consider. Remember
the funny shader programmer? He decided to
omit every light that is NOT on his list. That’s a
strange attitude, but not stranger than the other
stuff in the parti_volume, no ? So we need to
link every light on the light list (Fig08). You can
either put in the (case sensitive!) name of the
light, or mmb drag and drop the light transform
from the outliner onto a spare field (you need
to re-select the parti_volume each time you
connect one light, so the mechanism can add
another open slot).
Fig 12
9. Now that we have this part running, lets
think about adding a few details that would add
more to the underwater impression. In Maya
we fortunately have the Paint Effects system,
which is easy to use and even has some built-in
‘underwater’ brushes (Fig09). I used some sea
urchins here and there, a hint of shells, and a
few scattered starfish. I also added a little of the
seaweed to some corners.
10. To be able to render the Paint Effects with
mental ray we need to convert them to regular
polygons (Fig10). I also converted their Maya
shaders to mental ray mia_materials, which
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Chapter 06 Underwater
Fig 13
is always a good idea to obtain a consistent
shading behavior across the scene, since in our
case everything else is built with them as well.
This needs to be done manually however.
11. That’s it; we’re finally ready to render. I used
a fixed sample rate of 2/2 this time (Fig11).
This is quite a brute-force way, and you might
consider using an adaptive sampling of 0/2, but
be advised to tune up the sampling of the area
lights along with it, since they are all left at 1/1
right now. Also you should consider lowering
the parti_volume step lengths if you encounter
artifacts with the adaptive sampling. It is also
worth mentioning that to actually ‘cast’ a shadow
into the volume, we need to have a shadow (and
Fig 14
general max-) ray trace depth of at least 4.
12. For the indirect illumination I chose a rather
low-quality appearing final gathering with diffuse
bounces (Fig12). This time, due to the volume
stuff, the final gathering will not add all too much
to the image, but it still has a nice contribution to
the general look of our piece.
Before we push the render button we need to
chant the gamma mantra though, as always.
Since we want our image to look nice, natural
and appealing, instead of dark, smudgy and
cg-ish, we need to pull it from it’s default color
space, i.e. mathematically linear, into the one
we are used to seeing, i.e. gamma corrected
Fig 15
sRGB. There’s a deeper explanation on this
matter in the very first of the tutorials, the
sunny afternoon. To recall the essential basics
however, lets repeat why we need to care about
the gamma issue BEFORE we render out our
image. As mentioned, the (any) renderer does
it’s internal calculations in a mathematically
linear manner, which generally is a good thing.
We could pick this truely linear result and
take it into our post application and gamma
correct it there (because gamma correction
/ putting things into the sRGB color space is
desirable in almost any case - probably almost
everything you see, i.e. photographs, pictures
are in this sense, already gamma corrected.
When using regular image files, which usually
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have the sRGB/gamma correction ‘baked’ into
Fig 16
them a priori, we need to remove this gamma
correction, before we RE-apply it on the whole
image. Makes sense, no ? I know its confusing,
but unless you dont want to have doublegamma-washed-out-looking textures we need
to obey this little rule. Applying the right gamma
on the whole image afterwards isnt enough, if
we want the textures to look as they should (i.e.
as we are used to seeing them, in their sRGB
color space). Now, many people dont care
about this whole issue and thus render in the
plain mathematically linear space. They wonder
why their images look strange and unnatural,
and have this unusual dark and smudgy look
and blown out highlights and overbright areas
everywhere. Realtime 3d has yet to ‘learn’ that
mathematically linear rendering is not what
the eye is used to seeing in nature (the human
brain reaches a ‘gamma corrected’, or rather
logarithmically corrected image too, if you will!
Although human perception is far more complex
of course).
13. So we want to have it gamma corrected/
sRGB. Our renderer mental ray has a built-in
function to automatically ‘remove’ the gamma
from the textures before rendering, and apply
the inverse of this gamma on the rendered
pixel/image. To do so, we go to the Primary
Framebuffer tab in the render globals and put
the appropriate gamma value, which is 1/2.2 or
0.455, into the Gamma field (Fig13).
14. As a last enhancement lets turn on
the ‘detail ambient occlusion’ mode of our
mia_materials. It should all be set up already
by default, we simply need to switch it on by
selecting the mia_materials and raising the
Ao_on value from 0 (off) to 1 (on). We can do
this easily for all selected shaders at once by
using the attribute spread sheet (Fig14), from
the Window> General Editors> Attribute Spread
Sheet menu.
15. We should come up with a render similar
to (Fig15). I rendered to a regular 16bit image
format, and took it into photoshop for some
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Environment Lighting
contrast and color adjustments. That’s the most
enjoyable part of it.
16. After playing around with the white balance,
crushing the blacks, enhancing certain color
elements (i.e. the blues and aquamarines),
and after having fun with the ‘liquify’ function in
Photoshop I came up with my final interpretation
(Fig16). I also put a ‘dust/grime’ image on top
of the image, to support the feeling of a thick
medium. I hope you like it.
And I hope you enjoyed following our
environment lighting tutorial series, as it is time
to say good bye for the time being. I have had a
great time solving all the problems concerning
each of the tutorials, and most defintely learned
a lot along the way, and hopefully you have too.
If you have any questions, criticisms, comments
or any other input on the tutorials, don’t hesitate
to contact me.
Originally Designed & Modelled by
Richard Tilbury
Tutorial by:
Florian Wild
For more from this artist visit:
http://individual.floze.de/
Or contact them:
mymail@floze.de
Introduction:
The aim of our training DVD’s is to provide the artist with the most comprehensive set of lessons available. This is
achieved by presenting the training material in the form of:
- step-by-step tuition.
- on-screen visual and audio instructions.
- ongoing forum support from the author.
- full-screen resolution flash movies.
All aspects of creating the finished projects are taught in a way that artist of all levels will be able to learn at their own
pace. Once these techniques have been learnt , they can be equally applied to all your future modelling and texturing
projects.
- Section 1: The Basics - Using the Interface.
- Section 2: Modelling - Head, Nose, Horns & the Eyes.
- Section 3: Mapping & Unwrapping.
- Section 4: Texturing - Painting Skin, Eyes & the Horns.
- Training by in-house 3D Artist Richard Tilbury.
- Over 3hrs 30mins of comprehensive training.
- Printable step by step PDF.
- Suitable for all levels of artist.
- Section 1: The Basics - Using the Interface.
- Section 2: Modelling - Head, Nose, Horns & the Eyes.
- Section 3: Mapping & Unwrapping.
- Section 4: Texturing - Painting Skin, Eyes & the Horns.
- Training by Julian Sarmineto - Sony Picture Imageworks.
- Over 3hrs 30mins of comprehensive training.
- Printable step by step PDF.
- Suitable for all levels of artist.
- Section 1: Modelling.
- Section 3: Mapping & Unwrapping.
- Section 4: Texturing.
- 8hrs 30mins of comprehensive training.
- Suitable for all levels of artist.
for more products in our range visit http://www.3dtotal.com/shop
: volume 2
Available Now Only!
UK - £32 USD - $64 EUR - €49
Features 58 of the finest digital
2d and 3d artists working in
the indusrty today, from the
likes of:
Philip Straub
Jonny Duddle
Alessandro Baldasseroni
Benita Winckler
Fred Bastide
James Busby
Marek Denco
Patrick Beaulieu
Jonathan Simard
Buy the book to see just
how they create their
incredible imagery!
for more products in our range visit http://www.3dtotal.com/shop
Hardback 21.6cm x 27.9cm in size
288 Full Colour premium paper pages
Introduction:
The ‘Eva Wild Series’ – Our aim in this series is to provide comprehensive lessons to produce a complete fully
rigged, textured and anatomically correct female character. This series fits well into 3 DVDs with 3 separate
professional 3ds Max instructors taking you through each
if their specialties in very detailed step by step processes
making this training suitable for artists of all levels.
Part 1 - Modelling:
- Complete step by step modelling of the Eva Wild character.
- Teaches the importance of studying human anatomy.
- Provides clear diagrams showing muscle flow and bone structure.
- 14 hours of comprehensive training.
- Suitable for artist of all levels.
Part 2 - Texturing, Mapping & Clothing:
- Complete step by step texturing process of the Eva Wild
character.
- Modelling and Texturing of Eva Wild garments.
- Lighting the character.
- 4 hours and 47 mins of comprehensive training.
- Suitable for artist of all levels.
Part 3 - Rigging & Animation
- Complete step by step of setting up a fully animatable
rig for the Eva Wild character.
- Creating a walk Cycle.
- Creating a simple face morph.
- 7 hours and 43 mins of comprehensive training.
- Suitable for artist of all levels.
for more products in our range visit http://www.3dtotal.com/shop
Introduction:
Michel Roger’s famous ‘Joan of Arc’
tutorial re-written for Maya by Taylor
Kingston, Cinema 4D by Giuseppe
Guglielmucci & Nikki Bartucci,
Lightwave by Vojislav Milanovich and
Softimage by Luciano Iurino and
3DCreative Magazine.com.
If there has been one single tutorial
that has educated and inspired more
budding 3d artists than anything else,
this complete step by step project by
Michel’s must be it. The community
is in debt to him.
These 120 plus page, Downloadable PDF’s are
designed for ease of use to help beginners and
intermediate level of artist alike in the creation
of a female character. The tutorial takes you
through the process of modelling, texturing and
mapping to finally adding bones.
for more products in our range visit http://www.3dtotal.com/shop
Image by Michel Roger
Chapter 1: Modeling of the Body
- Body
Chapter 2: Modeling of the Head
- Head, Ear & Assembly
Chapter 3: Modeling of the Accessories
- The Sword & Armour Legs
Chapter 4: Modeling of the Accessories
- Armour Bust, Hair & Glove
Chapter 5: Modeling of the Accessories
- Accessories & UVW Mapping
Chapter 6: UVW Mapping
- Sword, Clothing, Armour & Body
Chapter 7: Texturing & Hair
- Eyes, Skin & Hair
Chapter 8: Bones & Skinning
- Bases, Hierarchy & Skinning
Introduction:
A Collection of the finest independent animated
movies and commercial trailers. The DVD includes
work from a whole number or different sources,
such as students, independents animators and
commercial studios. We want people to be able to
view this wealth of elite animation in one convenient high resolution package whilst generating
much exposure for these talented artists at the
same time.
- Running Time: 3hrs 8 mins
- 27 Shorts movies
- 6 Clips & Trailers
- Region Free, NTSC & PAL versions
- Shorts & trailers from artist and studio like:
Blur Studios
Brian Taylor
Marco Spitoni
Patrick Beaulieu
& Alex Mateo
- Running Time: 3hrs 8 mins
- 27 Shorts movies
- 3 Trailiers
- Region Free, NTSC & PAL versions
- Shorts & trailers from studios such as:
Blur Studios
Keytoon Animations Studios
Redrover Studios
& Platige Image
- Loads of extra including images and storyboards
for more products in our range visit http://www.3dtotal.com/shop
Downloadable Tutorial EBook
Introduction:
The original character of the Swordmaster
was created by Seong-wha Jeong and we
had 3DTotal’s in-house 3d artist Richard
Tilbury, re-create the character in 3dsmax
as well as create the textures in Photoshop,
in our new precise, step-by-step tutorial for
highly polished, low polygon game character
with detailed texturing for real-time rendering. We have also converted the tutorials into
Cinema 4D, Maya, Lightwave and Softimage
platforms. Even if you are not a user of one of
them, the principles should be easily followed
in nearly all other 3D applications.
The Swordmaster tutorials is spread over 8
Chapters which outline, in detail, the process
for creating the Swordmaster below are the
details.
image by Seong-wha Jeong
Chapter 1: Modelling the Head
Chapter 2: Modelling the Torso
Chapter 3: Modelling the Arms & Legs
Chapter 4: Modelling the Clothing & Hair
Chapter 5: Modelling the Armour
Chapter 6: Mapping & Unwrapping
Chapter 7: Texturing the Skin & Body
Chapter 8: Texturing the Armour & Clothing
for more products in our range visit http://www.3dtotal.com/shop
THEBRANDNEW
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