There is a cheaper option for a payload camera than a GoPro or Canon Powershot, the Raspberry Pi. This option is very simple to implement and provides a cheap, light, high resolution option for HAB teams. The Pi Camera module can take 5MPixel stills or record 1080p video at 30fps. A 32 GB microSD card will allow you to film for 5+ hours at 1080p. If you record for a few minutes (to limit file sizes) and then take a 5MP still and then repeat continuously for the flight you will get a good combination of high resolution stills and video.
Raspberry Pi B+ and Raspberry Pi HD Camera can be bought from RS with fast delivery in South Africa for R850 (price quote 2 March 2015)http://za.rs-online.com/web/p/processor-microcontroller-development-kits/8111284/ http://za.rs-online.com/web/p/video-modules/7757731/?origin=PSF_437599|rel
The Raspberry Pi will require a separate battery to power it and you will need to buy the microSD card separately. The Raspbian linux distribution for Raspberry Pi comes preconfigured with the software to control the camera. You will need to create a script to control the camera operation through the flight.