Stereo Photography With A Single Camera - Canon Camera Hackers Manual

7.7.1 Stereo photography with a single camera

What works for a chicken can work for us, too. It isn't really necessary to use
two cameras for creating stereo images. If the subject matter doesn't
move, you can obtain good results by using a single camera: take the first
shot, move the camera a bit to the right, and take the second shot. This
method is particularly suitable for macro stereo photography. In macro
photography, the shift between the left and the right image must be quite
small—so small that it's impossible to mount two cameras side by side
without exceeding the optimal distance between the two lens centers.
Shifting a single camera, however, sounds easier than it is. It can be
quite hard to make both images register correctly, especially when shoot-
ing hand-held. The SDM offers ( just like the CHDK) the Edge Overlay as an
aid:
First, switch on the Edge Overlay by clicking the
f
pressing the FUNC/SET
tice such as "Allocated xxxxxx bytes". Press
mode.
Press the shutter button a first time. The Edge Overlay should appear
f
now in the form of bright yellow lines. Also, the message "frozen" is
shown.
Move the camera a bit to the right, but not too much. Use the distance
f
between your eyes as a guide and also see below. For macro work you
can choose a much smaller distance, and for landscape work you can
exaggerate the 3D impression by choosing a larger distance.
Now register the camera so that the edges of the nearest subjects
f
match. The difference between the edges of the farthest objects ( devia-
tion) should not exceed two millimeters on the screen (assuming a
display width of approximately two inches).
Take the second shot.
f
Now switch to Replay mode. Navigate to the first (left) image and half-
f
press the shutter button
image and half-press the shutter button again. The display should now
show a red/cyan overlay of both images ( anaglyph). If you have your
red/cyan goggles with you, you can view the image in 3D right away.
Under ALT > MENU
monochrome anaglyph, a color anaglyph, or a side-by-side pair.
The main purpose of this display option is, however, to check the
registration of both images. If you want to magnify the anaglyph, you
must first zoom in on the left image, half-press the shutter button, then
3 On the S2 IS, S3 IS, S5 IS, and A550, use
button half-press.
button for a second. You should now see a no-
3
to select it. Then navigate to the second (right)
> Stereo > Playback mode you can choose between a
FUNC/SET
ALT button and then
ALT again to leave the <Alt>
instead of the shutter
7.7 Stereo photography
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