FHALP-2 had a separate camera which was mounted in its own payload case and hung below the main payload. It was an Olympus Mju 300 with a 555 timer (set to pulse every minute) which was rigged so that it was powered by the main battery and triggered the shutter. While it was a little difficult to set up it worked excellently throughout the flight.
A little investigation has revealed that it is possible to put a temporary firmware on an SD card for Canon cameras which will allow you to run scripts. This has been used by EOSS to set up the camera and then take pictures every 20 seconds - all the launch team need to do is turn on the camera. I plan to do this for FHALP-3 with a Canon A610 5MP which I'm getting off Ebay