Darktable uses libgphoto2 for tethering, you can find a list of by libgphoto supported cameras here.
Tested and fully functional cameras
Here follows a complete list of verified and supported cameras for tethering with Darktable...
|Canon EOS 40D (PTP mode)||2.4.10|
|Canon EOS 400D (PTP mode)||2.4.8|
|Nikon DSC D60 (PTP mode)||2.4.8|
|Nikon DSC D90 (PTP mode)||2.4.8|
Verify support for your camera
Your camera must be fully supported by gphoto2 and before reporting any problems about camera tethering, the following steps must successfully performed.
First of all be sure to have gphoto2 tools installed, then connect your camera to your computer using the usb cable...
1. Verify that camera is detected
The following command will provide which cameras are detected and connected to the computer, find your camera port name and use it in the tests below ( mostly port usb: will be enough )...
env LANG=C gphoto2 --auto-detect
2. Verify camera driver abilities
Execute the following command and verify that the "Capture choices" ability supports Image and "Configuration support" is yes. These two abilities is checked and decides if "tethered shoot" button should be shown or not in Darktable.
env LANG=C gphoto2 --port usb: --abilities
3.a Verify camera remote capture
This step should capture an images and download it to your computer.
env LANG=C gphoto2 --port usb: --capture-image-and-download
3.b Verify camera tethered capture
And last this step waits for you to push the shutter trigger on camera then the images should be downloaded to your computer.
env LANG=C gphoto2 --port usb: --capture-tethered
Soo now what?
If you successfully went thru all the tests above your camera will likly be supported by Darktable and tethering, if you anyway stumble into a problem in Darktable please file a bug @ http://tinyurl.com/dtbugs and attach outputs of the 2 steps above and the log of:
darktable -d camctl 2>1 >camctl.log
If any of the steps above failed, there are problems with your specific camera and driver, please report the issues to gphoto2 mailing list for further help, include these flags to the command above that failed to attach to the mail for better support:
--debug --debug-file gphoto2_debug.log