Originally Posted by dinos_gr
How long would you think that a 2gb card could record running on a 680x480-30fps resollution?
On average, that's around 2MB per second. So that would fill up a 2 GB card in 1000 seconds, or about 16.66 minutes. Considering most videos are around 5 minutes, that's enough, but they're usually cropped down from at least an hour of footage.
It's really the Bit rate that matters. You could be standing still, and it would hardly take up any disk space. The faster you go, the higher the bit rate.
Hopefully the device will have a bit rate setting as well as a resolution size setting.