ZWO ASI 178 Banding (possibly resolved...)

[Davesellars]

I've been using this camera (mono version) for about 10 days and have had quite a few opportunities to use it (see my EAA Reports thread) and seem to be experiencing banding on the camera that to me ruins some of the images.  I've used flats most of the time using Sharpcap to generate them which also creates the bias and darks (not all the time, depending on what i'm capturing or have changes my settings and just testing...

Anyone else with experience of this camera state their view of the banding I'm seeing.  is this normal or is the 178 just particularly bad in this case (which is shame as the camera is really sensitive and capturing nice images).

EAA captures

 

Edited October 20, 2022 by Davesellars

[Davesellars]

OK, so just testing out (it's cloudy tonight!) in Sharpcap and having just taken dark frames for 8 second subs @ 200 gain the banding still really shows up actually even more significantly...

 

[tomato]

I have used ASI178 mono cameras for a few years for DSO imaging, exposure times ranging from a few seconds to 3 minutes and I haven’t encountered the banding effects that you have reported. The cameras are currently not in use but I’ll plug one into NINA and let you know what settings I am using.

A couple of other points that might be significant, the cameras are retro fitted with Peltier coolers to keep them at a near constant temperature (3-4 deg C) and I use after market USB 3 cables rather than the flat cables supplied with the camera.

[Davesellars]

Many thanks!  That's interesting about the cooling.  The first couple of nights I used it was particularly cold and I think the camera was reporting 10 degrees and I didn't see the issue quite so much.  A couple of nights ago the temp was around 14 - 15 degrees.  I've tried both with the supplied USB3 cable and also a good quality USB3 cable I've been using outside and there's no real difference.

Would lack of cooling cause quite so much of issue of banding?

[tomato]

I’m not sure, I just mentioned it because it is a difference between the cameras. They were fitted to make the application of calibration frames more consistent, given the significant amp glow that is inherent with the 178.

[Davesellars]

So the problem doesn't appear to be the camera nor the offset which I originally suspected.   Using ASIStudio capture I don't see any issue and also with SharpCap taking an individual capture rather than LiveStack also I can't see an issue - one I've stretched it using StarTools.  Using Livestack though in SharpCap, the problem appears immediately.

Edited October 21, 2022 by Davesellars
re-assessed issue