9.12.11
no notes
Camera Obscura Lab
due tomorrow
Today:
Recap for lab
Optical Illusions
Data calculations
•
•
•
•
Hi is negative –upside down
Ho positive
M negative--<1, has no units
Di = 23 cm
• All of the numbers in the same units
M = hi = - di
ho
do
hi
ho
di
do
Rays are straight lines of light
Notice that the rays from each edge of the object cross exactly at the
pinhole when it is very small
Be sure to draw in the image in the diagrams!!
M = hi = - di
ho
do
hi
ho
di
do
When the pinhole is larger, More rays enter the pinhole
from each spot on the object, What effect does that have
on the image?
Would the image be more or less clear?
Would the image be more or less bright?
Conclusion..3 parts of purpose
Confirm the linear propagation of light
Calc. Magnification
Calc. the Height of object
3-D Images
Stereoptics
Here you can see the two photos that
the stereoscopic viewer helps your
brain to process as a single 3D image.
Floating finger illusion
• The Floating Finger
• Hold together the ends of a finger from each hand
about arms length in front of you. Look under your
fingers at some distant object. The fingers will now
appear in three sections. Separate the fingers slightly
and a finger with two fingernails will seem to be
suspended between your two fingers
Stereoptic photos
Cross your eyes to view these images in
stereo 3D
• Cross your eyes to view these images in
stereo 3D
•
1280
Stereoptic
•
The treehouse bridge from the other side
1280
• A path to the treehouse
Optical
illusions
Impossible stuff
The Falling Ball illusion : Is the ball
really going down ?
Waterfall : Where does the water falls ?
Evanescence of Love
Impossible figures
• How long would
the heart
carved on the
tree last?
Crazy Gymnasts
Impossible figures
• Can you spot 3 problems with what's going on
here
Illusion in or out?
Whats up??--illusion
"Flowers"
"Image in
the
Pattern?"
"Image in
the
Pattern?"
Optical illusion
You should
see a girl, a
wolf and a
waterfall
8 Faces Scenario : Can you find them all ?
Another Art Illusion
The Natural Baby
Flowers : Are they really just flower on the eye illusion?
Look for the hidden faces.
Don Quijkote : Look closely. How many faces are there ?
Hidden Tigers : How can you find ? Concentrate
Horses and the Nature
The General's Family : There are 9 People in the picture
below. Try to find them.
The Pirates : There are 11 faces in the picture below.
How many of them can you find ?
Wolves : Can you find them ?
The Animal Kingdom : How many living things can you
find in this picture? Possibly All !!!
Optical
illusions
Compare the size
and shape
Larger?
Straight?
At first, there doesn't seem anything unusual about this
picture.
Skewed lines
All these tracks look as
though they've
come from a
broken down
railway track, but
in actual fact, they
are perfectly
parallel! To prove
they really are
parallel, watch the
small 'hairs'
gradually
disappear. You will
see the lines as
how you would
expect them to be.
All of the
red lines are
completely
parallel
would you
believe?
Illusions – size in perspective
Square or not?
Lines straight??
Size of dots
OPTICAL ILLUSIONS
After Images
After Images
• You should see a negative version of the square
and word. Note that the image does not show up
instantaneously but emerges out of the gray in a
fraction of a second or so. Then it slowly fades
away.
HERE is a chromatic diagram
with roughly equal luminance in all the squares
(except yellow). Look for its afterimage the same
way, by staring at one place in the middle of the
pattern for 15 seconds and then shifting to the gray.
Rapid-eye-motion
• Stare fixedly at the black dot for
30 seconds, and then look at
the white dot. The black
squares should seem stationary,
but the white afterimage will
flicker about, revealing your
rapid-eye-movement. The
afterimage is "burned" into
your retina, while the new
image is flickering about on the
retina due to the REM.
Optical
illusions
Apparent motion
Flickering Fog
illusion
•
stare intently at the red dot in the center of the left block for about a couple of
minutes.Once you've done this, look over to the center of the right block. It should act
weird - by fading out and 'flickering'. If you move your head closer and further from the
monitor (while focusing in the center), you should see some interesting interference effects
too.
Wheel of
Confusion
Which way is
the wheel
turning!?
• it appears to be
rotating anticlockwise.
However, if you
follow the
yellow dots
round instead,
the whole
wheel will be
turning the
other way! clockwise!
• Wow! Try staring
at this for more
than 5 seconds
without going
crazy. Then try
following it round!
=)
Curves constantly
die out and then
re-evolve as
part of another
curve.
Rotating dot whirlpool
Primrose's Field : This checkered background consists of
squares but appears to wave. In addition, this figure shows a
great amount of anomalous motion illusion.
The Rotating Dots : Follow the movement of the rotating
pink dot with your eyes and the dots will remain only one
color, pink. But if you stare at the black + in the center,
then the moving dot will turn green.
Vanishing Dots : If you stare closely at one yellow
dot for a while the other dots disappear.
Magic Zoomster
This cool optical
illusion has been
seen before, but
I've spruced it up
by adding colour,
multiple layers,
and making it
bigger!! The idea
is to focus on the
dot in the centre
and then move
your head
constantly
towards and
away from the
monitor. You
should see the
circles rotate
spookily! Press
the F11 key in
your browser to
see the illusion at
full screen!