Canon Camera, Hackers Manual

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C H A P T E R 7 The Stereo Data Maker (SDM)
If you are skilled, you can build such bars by yourself. You can certainly find
instructions on the Internet, for example at
http://3dbruce.blogspot.com /.
Another option is to acquire a ready-made bar from a manufacturer, for
example at
www.digi-dat.de/index_eng.html.
Finally, if you want to shoot in portrait orientation, you need a U-frame
to mount both cameras.
The SDM supports all of these mounts. Under ALT > MENU > Stereo > Cam
orientation, you will find the options H (for a horizontal mount), V (for a
90-degree mount), and I (for a 180-degree mount). Under
ALT > MENU >
Stereo > Cam rotated, you will find the options L (to the left) and R (to the
right). For each mode, the camera will present the SDM menus and the
SDM OSD with an appropriate rotation (0, 90, 180, 270 degrees). Even the
LEFT , RIGHT , UP, and DOWN buttons are swapped accordingly. The native
camera menus, however, will remain unchanged.
You also have to identify the position of each camera under ALT >
MENU > Stereo > Twin-Cam position with L for left and R for right. Some
functions will behave differently for left and right cameras.
You can get all of this set up for you by using one of the ready-made
configurations (section 7.1) contained in the SDM distribution.
Registering
Registering two cameras is, of course, a bit different than working with a
single camera. For example, you will not be able to use the
Edge Overlay or
to view the result as a composite anaglyph on the camera display. The two
cameras simply cannot exchange their image data. However, we can rely
on grids and on the deviation indicator. The rules used for determining the
Camera Spacing and the Deviation Factor are the same as when working
with a single camera:
f
Set the camera’s AF mode to Center .
f
Under ALT > MENU > Stereo > Camera Spacing, dial in the distance be-
tween the lens centers of both cameras.
f
In the same menu, specify a preferred Deviation factor (section 7.7.1).
The maximum acceptable deviation dmax is computed by dividing the
image width by the deviation factor.
Figure 7-11
The Z-frame can be used to mount two
cameras as close together as possible.