30Hz for full-frame CMOS scanning (512 x 512 pixels), and up to approximately 600Hz for a sub-scan of 100 x 100 CMOS pixels. Increasing the read rate to 600Hz from 30Hz will allow brighter objects to be imaged, extending the dynamic range by more than 3 magnitudes.

At all these rates, the background in a single CMOS scan is basically a bias frame, as there is too little time to allow any appreciable build-up of dark current. The local background bias surrounding a photon event is then estimated by the Electronics Unit, and is necessarily corrected for in the calculation of the centroid. In order to mimic an integration-style data collection, we have included an imaging parameter to slow the scan rate of the CMOS by inserting a gap-time (i.e. a delay) between read scans of successive CMOS rows. The result is that when starting an imaging sequence, the first image will have a ramp-up to the total integration time by the end of the last row-read, but successive frames after that will all have equal integration times for each CMOS pixel row. This is not as ideal as integrating the entire frame at once and then reading it all 