[glend (Glen)]

Ray thanks for that comparison. The amp glow in the 1600 is, as i understand it, dependent on the driver and perhaps on the camera firmware revision being run - they may not be the same thing. Can you tell me which driver version applies to your dark test below?
Re Firmware, I believe that my 1600 is running the ASI1600CoolFpga_V1.104.vme firmware upgrade (dated 15/06/16), as Sam installed that during my Teamviewer session. I also have what appears to be the previous file ASI1600Cool_V1.102.vme (dated 9/3/16), in a release folder he left on my laptop. I do not know if this firmware makes any difference to amp glow.

For comparison purposes I can supply you with a 300 second Unity dark file (@-25C), which I have been using and which was shot after the upgrades applied by Sam. I also have a Master Dark built with the same dark files if that is preferred. Interestingly, the individual 300sec dark FIT files, viewed in FITS Liberator at pixel level, show eleven white pixel spots (hot pixels) scattered around the frame, which are removed during DSS processing to Master Dark (with hot pixel detection/correction turned on).
A review of my other individual FIT Dark files shot at 60, 90, and 120 seconds show significantly less noticable hot pixel presence. Unity seems to have an influence as well as compared to less Gainy settings. For LRGB imaging the hot pixels would not be a concern but for narrowband they do show up but are easily removed during Master Dark processing. Do other people have these in their individual Dark files?

When I stretch my 300s dark files they do seem darker on that right side boundary, which is where it had appeared previously, but obviously a histogram comparison might tell more than my old eyes and an undetermined stretch.
I am unequipped to evalutate the differences in the firmware releases but will ask Sam for some notes about what any differences might be. If you would like a copy of one of my dark files just PM me your email address and I will send it to you (31meg), or I can load it into the file sharing area of Astrobin..