Qhy268m flats routine

[assouptro]

Hi starfolk!

I hope one of you with experience or brains can help me out? 

I am trying to find out the best way to produce a decent flat with my qhy268m 

My first light images were taken in mode 0 gain 26 offset 25 as that was the default with Nina and I haven’t done all the research on mode/gain/offset yet as it’s quite confusing 

with my Atik ccd’s I have a dimmable flat panel, set up a looping image and adjust the brightness until I’m around 26000 adu then tick the save box allowing 30 frames to be saved (couldn’t be easier!)

Now I have Nina flat wizard, which is new to me too, telling me it’s too bright or too dark then finally settling but producing flats with horrible vertical banding 

What am I doing wrong? 
 

master flat of 30 frames 

Many thanks 

Bryan

Edited October 21, 2022 by assouptro
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