ZWO 2600MC banding / calibration problems

[AbsolutelyN]

I received a ZWO 2600MC last week and managed to get it out for a few test shots this evening. 

However I'm struggling with calibration. I've never used a OSC camera before and am getting some odd results. I'm hoping I'm missing something obvious.

I've got bias and darks (I don't have flats). Those are applied to the lights with image calibration in PixInsight. The calibrated lights are debayered with RGGB. Then star aligned and the aligned lights integrated. 

The same thing happens if I debayer, align and integrate without darks/bias. 

I'm getting green/magenta banding. The files look fine initially - the banding becomes clear once you run a DBE. Anyone got any pointers on what I'm doing wrong? 

With saturation through the roof to make it more obvious:

 

Flat

Many thanks

 

Edited November 9, 2020 by AbsolutelyN

[AbsolutelyN]

Still can't figure this out. Have  retaken all the darks (120 darks) and bias (400 bias) frames, integrated in every way I can think of and every time ends up with the same green/magenta banding.  Admittedly it's only visible when you really push the files but I dont get anything like this with my 1600MM. Full frame with no crop from a rasa 8. Any suggestions most appreciated.

pushed you can see banding

 

Edited November 6, 2020 by AbsolutelyN

[Ken82]

I think you should try calibrating your flats with dark flats and then calibrate your lights with the master dark and master flat. 
 

I believe this is the best method for cmos cameras. 
 

ken 

[tomato]

I’ve got the same scope, sensor(QHY 268c) and target, (180 x 60 sec). I took flats and dark flats today, as soon as I have some darks, I’ll attempt to process the lights and let you know what I find.

I have found on-scope darks hard to do with a RASA as the cover on the scope stops the camera cooler dissipating heat so it cannot maintain the temp set point.

[AbsolutelyN]

1 hour ago, tomato said:

I’ve got the same scope, sensor(QHY 268c) and target, (180 x 60 sec). I took flats and dark flats today, as soon as I have some darks, I’ll attempt to process the lights and let you know what I find.

I have found on-scope darks hard to do with a RASA as the cover on the scope stops the camera cooler dissipating heat so it cannot maintain the temp set point.

Thanks. I can make my files available for comparison if needed (I'm worried I'm just not getting the calibration process right).  All 120 sec exposures. I've not got any flats and have now removed camera for second set of darks. First darks were on well covered scope at night, second set with camera capped and covered in tin foil. Made no difference. Also have lights/darks at 100 gain and 0 gain and still have same results.  

Edited November 6, 2020 by AbsolutelyN

[AbsolutelyN]

Also the green / magenta bending doesn't seem match the bias or dark files - green/magenta seems more fixed width and regular

Bias


Dark:

 

 

Edited November 6, 2020 by AbsolutelyN

[DaveS]

I'm not sure about the IMX 571 cameras, but when I calibrate my 1600, 183, and even the SX694 I don't use Bias AND Dark, one or the other. The ASI 1600 and 183 absolutely MUST have Darks, but with no amp-glow you may get away without. For the low noise SX 694 I followed Terry's advice and only use Bias.

My understanding is that the Dark frame signal also contains the Bias signal, so you end up over correcting, if you add another dose of Bias on top, if that makes sense.

[Jonnycorvo]

Hi,

Recently i have bought the same camera ZWO ASI 2600 MC PRO. It's my first camera and i have the same problem as you. The vertical green and magenta banding.

Did you find a solution to this problem?

If yes, how did you solve?

 

Thanks,

Raffaele