[Kal (Andrew)]

Last night I did the firmware hack on my 840K Toucam to effectively make it a 900nc. The hardware is exactly the same, but the 900nc has the option to use the lower compression YUY2 codec. The hack went without a hitch, so I decided to do an experiment to see exactly how much less compression there was on my video captures. The following 4 captures were each for exactly 60 seconds:

5fps IYUV codec - 133MB
5fps YUY2 codec - 180MB

10fps IYUV codec - 270MB
10fps YUY2 codec - 234MB (dropped ~200 of the 600 frames, about 34%)

Based on this data it, you can clearly see how much less compression there is between the YUY2 codec compared to the IYUV codec. However, it appears to me as though there is no difference in compression rate when moving from 5fps to 10fps. When reading Mikes planetary imaging guide I was under the impression that there was higher compression when moving from 5fps to 10fps, but this data doesn't seem to show that. Am I missing something here?

Based on this data, I would say my best option would be to capture at 10fps YUY2 codec in good seeing, accepting the frame loss as I still capture 33% more frames when compared to 5fps. In poor seeing I should capture at 10fps IYUV codec for no frame dropping, to capture more frames with higher compression.

Thoughts? Comments?