3D –graphics and animation
Cameras and lights
Harri Airaksinen
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Camera types
 Modeling systems have their default camera
(perspective view). Camera can be rotate, zoom …
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Camera types
 Target camera
(location –
target)
 POV = Point of
View
 Free camera
Camera is located by
pointing, direction
is the viewport
direction
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Focal length
Focal plane
 Focal length -[live area],
area, where cameras
properties/controls make it
possible to see 3D –objects
through camera
 Focal plane, plane fixed by
cameras lens, where 3D
environment can be seen
nicely
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Seeing through camera
How to present the viewport?
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The depth of field
 Lens/cameras feature, what area in 3D environment
can be seen nicely
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Camera controls –
3D Studio Max
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How to use cameras?
 Point of View Shots; directly
to the target, many cases
height of persons eyes
 Low Angle and High Angle
Shots
 Reverse Angle Shots
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How to use cameras?
 Close-Up Shots
 Medium and Wide Shots
 Long Shots / Tele Shots
[ Computer Graphics, Principles and Practice; James D. Foley, Andries van Dam,
Steven K. Feiner, John F. Hughes ]
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Camera lens types
 Common 3D modeling tools have
wide collection of lenses (and you can
build your own)
 Note! Real photography light sensible
film must places to projection plane

In 3D environment simulated cameras
projection plane can be anywhere
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Camera lens types
Type
Focal lenght
Fisheye
7,5 mm
Extreme Wide Angle
18 mm
Wide Angle
28 mm
Medium Wide Angle
35 mm
Standard / Normal
50 - 55 mm
Medium Long
80 mm
Long / Telephoto
135 - 250 mm
Extra Long / Super
tele photo
500 mm or more
• offers an adequate 46 degree
angle of view with very little
perspective distortion and with
average depth of field ->
useful for medium to wide
shots.
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Camera lens types
 A wide angle 24 or 28 mm lens supplies a 83 degree angle of
view, outstanding depth of field, but also a small amount of
distortion on the edges of the picture due to the forced
perspective projection typical of the wide angle of vision.
 A telephoto 135 mm lens has
excellent abilities for close framing ->
flattens the perspective and has a
narrow 5 degree angle of view and
a small depth of field.
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Lenses in generally – link between
focal length and the angle of view
 Lenses with a short focal length offer a wide angle of view and
increased depth of field, but objects appear distant to the
camera
 Lenses with a long focal length have narrow
angles of view and depth of field
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If you don’t change the lens, but
camera is moving – what happen?
 Camera is moving away from target:
 Image area is increasing
 The depth of field is increasing
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When both the lens and the point of view
are changed ?
 The subjects in the foreground of the image remain within a
similar scale as long as:
the focal length decreases or increases along with the distance between
the camera and the subject
 The projection of the background elements
is significantly different

[The Art of 3-D Computer Animation and Imaging; Isaac Victor Kerlow]
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Camera animations
 The camera has a powerful storytelling effect
because it leads the eyes and mind of an audience
through a story
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Camera animations and paths
 Camera movement is controlled by path (line, spline or some other 2D
object)
 Camera POV: down the path, targeted to point of interest, changing point
of interest or combination all of these
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Camera animations and paths
Select camera  motion  Assign Controller
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The use of camera and layout
- dramatic art  Use different cameras to tell the story and expressing the
emotion
 Keep the long straight lines in the composition parallel or
perpendicular to the edges of the image to avoid unwanted
tension and distraction -> the horizon or a tall tree in a
landscape tilting to one side especially when the tree is close
to an edge of the image
 The camera too close to an object may result in images
with large unfocused areas occupied by these objects ->
effect often overwhelms the rest of the image  emotion
(example. face is zoomed, only eye or mouth is seen)
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The use of camera and layout
- dramatic art  It is usually distracting to cut off the head of a subject in
a head shot or a portion of the object in a close-up shot ->
when done skillfully, cutting off portions of the main subject
can help the viewer focus on details -- such as the eyes or
the mouth, for example -- that may add emotion to the image
 When image clarity is an important issue, it helps to place
the main subject in a shot against plain backgrounds.
Backgrounds with dense textures or with a multitude of
objects and colors tend to take the attention of the viewer
away from the items in the foreground
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Lights and 3D environment
 Point lights
 Spot lights
 Linear lights
 Area lights
 Infinite lights
 Ambient lights
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Point light (Omni)
(an omni-directional light)
 casts light evenly in all directions . Example,
light bulb
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Spot light
 Cast light in a cone shape and only in one specific direction
 Features: a variable-angle cone of light and a light fall-off
factor. Example; Flashlight
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Linear light
 Linear lights have length but no width, and can also be
scaled to any size – example: The light of the fluorescent
tubes
[The Art of 3-D Computer Animation and Imaging; Isaac Victor Kerlow]
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Area light
 Some programs provide area lights in the form of
rectangular areas of light
 Area lights can be scaled to almost any size but are more
efficient when kept small
 Area lights can also be used to
simulate the reflection of light
coming into an interior space
through the open windows.
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Ambient light
 The light is distributed evenly throughout the entire scene  a
point light source that is created automatically by the program
for each scene. Some programs can simulate the sun
Simulating the sun, 3D Max
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Ambient light
 Even though an ambient light source can be placed in a
specific XYZ position in three-dimensional space -> an
ambient light is coming from all directions
 The ambient light source often determines the general level
of illumination, or shade,
of a scene and almost always
there is only one ambient
light source per scene
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Basic Components of a Light
Source
 All simulated light sources include:
 Position ( spot lights have orientation and cone angle )
 Color and intensity
 Decay and fall-off
 Glow
 Shadows
 Lights can be edited separately.
Some programs also allow to group
several of these attributes and save
them together in a file, called
a light shader
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Lights color and intensity
 Color
 Intensity, (how strong)
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Decay (light weaks down) and
Fall-Off (shadow soft part)
 The decay value of light controls the force of a light source
and how far from the light source the light travels:


A weak light decays rapidly
A strong light decays slowly and travels far
 The light created from spot lights, decays as it
moves away from the light source, but
also as it moves from the center of the beam
 Fall-Off
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Cone angel and light beam
- Glow Example. headlight
 The glow of a light is a circle
of light that forms around the
light source  the light is
refracted and reflected by
particles in the environment,
generally ice, dust, or smoke
 The glow of a point light
usually occurs as a circle or
halo around the light source
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Volume light
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Global and local lights
 Global = general lights for all objects. Default light with
default values
 Local = added lights, targeted some objects or parts 
creating effects
Using global light
Using local light
[Computer Graphics, Principles and Practice; James D. Foley,
Andries van Dam, Steven K. Feiner, John F. Hughes]
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Shadows
 All lights creates shadows
 You can select: use shadows or not
 Shadows outlook depends on shadows features,
objects features (shape, softness, transparency) and
rendering algorithm
 Shadows can be defined by several parameters:



color of the shadow
color of the penumbra
softness of the shadow edge
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Shadows
3D Studio Max
remember: light
shadows on
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Lighting the Scene
 Lightning is important  without adequate lighting, shapes,
colors, and textures can only be experienced halfway
 Using computer based lighting is interesting; you have
ambient light, everything else is based on your talent
 Theories behind scene lighting  drama to comedy 
different lighting
 Categories of lighting are:






the main action area
the secondary action areas
the backgrounds
ambient or fill-in lighting
visible light sources
moving lights
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Categories of lighting
 The main action area, where most of the action
takes place :



A couple of spot lights might be enough for a simple shot of a mostly
static scene
A several of point lights and spot lights might be needed to delineate
the motion of the characters running back and forth on the stage
Note! Number of cameras. Lights can be also turned off
 The secondary action area, place in the scene into which
some of the action eventually spills:

Most case not so many lights than the main area
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Categories of lighting
background and lights
 The background = the stage, the scenery, the surroundings :
 Scenery - especially backdrops with texture maps - is very
sensitive to colored light.
 The fill-in light = ambient light, and has the dual purpose of
defining the overall color tone of the entire scene. Created
with infinite light sources and also with spot lights
 Visible light sources are sources of light that can be seen by
the camera and the spectators, example. lamps, fireplaces,
reflectors, candlelight, televisions ..
 Moving Lights; A theater stage  emphasize something 
series of spot lights that are mounted on the camera and follow
the action by trailing the camera
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Lights changes as a time function Explosions
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