Sorry, I totally forgot about this thread, school work burried me under
Yes, the resolution at 1000FPS is quite low, and requires a lot of light. On the 1000FPS video, the laser looks dim, however in person it was unbearable to look at.
The reason the resolution decreases as the frame rate increases is simply processing power and current technology. The 30 second highspeed limit is also because of this.
At 1000FPS, the camera has to, well, record 1000 images per second. Since it's not possible to write to a SD card that fast, it uses internal storage. Once the video is done, it takes it from internal storage and dumps it on the SD card.
The highspeed cameras used by programs like Timewarp and Mythbusters are multi thousand dollar camera's, that have extremely fast data storage devices. This allows them to capture frames at much higher resolution.
However, we are comparing a $400-650 camera to a $10,000+ highspeed camera, of course it's gonna be no match, but it's fine for hobbyist use. 120FPS mode is perfectly useable VGA resolution.