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« on: July 16, 2017, 08:05:17 PM »
This mode is now supported in V0.2, both triggered exposure, where a rising or falling edge triggers an exposure with the exposure duration controlled by the camera, and shutter gating, where the external signal controls both exposure start time and exposure duration.
To use triggered exposure mode, set your desired resolution in Record Settings, and set maximum frame rate for that resolution. Go into Trigger/IO Settings and select Exposure Trigger for IO1 (BNC), turn off the pullup and debounce options, and set Invert based on your signal. With Invert unchecked, it will start exposure on the rising edge of the input signal, and on the falling edge if checked. The shutter control will continue to control the exposure duration in this mode.
Setup for shutter gating is identical as for triggered exposure above, except the shutter is entirely controlled by the external signal, the exposure slider does nothing. When the external signal is active, the shutter is open, and is closed otherwise.
Note that you can't do a black cal unless the camera is receiving a proper repetitive exposure trigger, so you may need to set the IO 1 function in Trigger Settings to None before doing a black cal, then set it back to Exposure trigger afterwards.
The delay between the external input going active and start of exposure is very small, under 1us.
There's are a couple of bugs that need to be fixed with this new functionality. There's a horizontal line artifact depending on shutter speed, try to make the exposure close to minimum or maximum to avoid it being in the center of the image. There's also a larger black offset on the first frame following a large deadtime of no frame capture, it starts to get bad beyond about 100ms or so, so it's best to keep your trigger pulse repetition rate higher than 10Hz on average. Both of these are on the bugtracker to be fixed.