I like to shoot a stereo photo with two Canon S5 IS with a base line (distance between the cameras) of several meters.
These could be 10 to 20 meters or even more. So wiring is not an option.
This is my idea:
On both cameras a script is running that get it's initial starting moment from the button of
an USB remote switch made for SDM. Now the scripts are waiting in intervals of - let's say - 15 sec each
while the cameras are placed on different tripods in a distance to each other.
A counter on the display shows the time left of the interval.
After an interval has ended, a new one starts immediately.
If I press a certain control button on the camera, nothing happens at first. But at the end
of the interval, a photo is shot. If I can manage to release the other camera before
the end of the same interval, I get a synchronised stereo shot, without directly
wiring both cameras.
The result may be similiar to this:

Would a mentionable time lag occur after several intervals?
Asynchrony of a few milliseconds wouldn't bother me.
Can Chdk read out the cameras internal timer?
The script could then get it's timing after each interval from the system clock.
Can anybody please elaborate whether this is possible or not?
I'm an eager script writer!

Best regards!
Sasha