Is there any way that I could interact with this script with a remote? I have a rig of 24x chdk cameras (yes, 24!) that I fire with a radio remote. At this stage to change the shutter speed I have to do it manually on all 24x cameras. Any thoughts?
Okay ... the attached script works and does what you want. But its technically a "proof of concept". Before I spent any more time on it I'd like to know what you think about the general concept of using the remote button this way?
Try the script out on one camera first? You can leave the USB remote parameter settings at their default ( Enable Remote [off], Switch Type [none], Control Type [none], Enable Sync [off] ).
When you try the script, a short on/off pulse on the USB remote switch will reset the shutter speed to 1/60 sec. If you push the switch twice, the shutter speed increases. If you push it three times, it decreases. Press just once at any time resets to 1/60. The size of the increase is a function of the setting in the parameter values (we can play with how big a step to take later).
If you hold the USB switch down for 1/2 second, the camera will do a "half press" and wait for the release of the switch to do a "full press" and fire the shutter.
As written, the sync will be on the order of a few hundred milliseconds. We can play later with having the camera immediately go to a full press status so that the USB sync function works when the remote button is released. This will blank the display and it times out after 60 seconds (if I recall correctly) so you can't hold the button too long waiting for the exact moment to take the shot.
We could also introduce a "two press" mode. That way you hold the button for more than 1/2 second to "half press" - setting focus and exposure lock at that point. If you release the button and quickly press again the shot will be taken (with precision sync). If you simply release the button then the sequence reset with no shot.
The shutter speed adjust currently does not recalculate the required ISO or Av value to rebalance the exposure - I'll fix that later.
Pressing the MENU key while the script is running will stop things in a graceful manner ( return to playback mode and disable the USB remote).
And obviously in your final application you would want to set the script up to "autostart" when the camera powers on. The script will switch into shooting mode on its own when started so you can start the camera in playback or shooting mode.
