Hi There,
Thanks for the post. In answer to your question, there are two different things going on here. First, there is exposure time, this is how long the camera allows light into the sensor, and this can be as short as 1ms (0.001s). Once the camera has taken the image though, it needs to start reading the image off the sensor. This takes a fixed amount of time, but is significantly longer than the 1ms exposure time. The software then needs to read the image from the camera, which adds a little more time to this part of the process. All in all, this means that although the exposure time can be short, the maximum frames per second is about 2-3. If you want faster frame rates and short exposures, then the Atik Titan or GP cameras might be a better option.
I hope this helps.
Chris.