I have an Atik 383L CCD. If I do Darks in the Atik softwarArtemis, I can set it so that the mechabical shutter does not open during the exposure. I would prefer to do Darks in SGP. If I set a sequence for Darks, does SGP ‘instruct’ the camera to keep the shutter closed during a Dark exposure. I ask because I did some Darks in Artemis and these were fine. I then tried Darks in SGP and found a bright area to the left of the resulting image. I have included a link to a 30 minute Dark captured in Artemis and an 8 second Dark (intended for use as a Flat Dark) in SGP. Ihope this demonstrates the issue.