Posted this on CloudyNights this morning, but I dont seem to have a lot of luck on that forum which is a shame as everyone seems really helpful on there..
My ZWO power supply showed up yesterday so I was able to start building a dark library for my new ASI1600GT while I wait for my filters to arrive.
My excitement soon turned to disappointment when I applied a screen transfer stretch in Pixsinsight to the first 360 second dark frame which revealed an almost vignette style amp glow.
Initially I thought it was light leakage so tried various things to completely rule that out. The last was to remove the camera from the scope, screw the cap on, place the camera nose down in wooden box, close the lid and drape the box with blackout material in a completely dark room - same result.
Is this really as good as it gets? My budget Canon EOS 2000D cost £290 and had no amp glow. $1700 later and I am swimming in it. Am sure it can all be calibrated out, but kinda gutted to have spent that sort of money to get this sort of result.
I emailed the photo below to ZWO who replied this morning to say this is normal and gave a link to a help article about calibrating out amp glow which I had already read.
Just looking for some reassurance really as it doesn't feel that normal having just spent $1700 on my dream astro camera....
Exposure time: 360 seconds
Gain: Unitary (139)
Offset 50
USB Limit 40 (I also tried 90 but it was the same).
Temperature -15c
Tried USB2 and USB3