Flat Issues - Broken Flat Field Generator?

[AndyThilo]

5 minutes ago, vlaiv said:

you can try the old flats with these new darks once you have time for it. It'll cost you nothing except a bit of processing time - you don't need to retake them.

Yeah I’ll try in the morning. Do I need dark flats?, I took them but not sure if I should use them?

[vlaiv]

Just now, AndyThilo said:

Yeah I’ll try in the morning. Do I need dark flats?, I took them but not sure if I should use them?

Yes, use a set of matching flat darks always.

[AndyThilo]

14 minutes ago, vlaiv said:

Yes, use a set of matching flat darks always.

Can I use WBPP? Do I just load them in with the flats? Or put them in as bias?

[vlaiv]

1 minute ago, AndyThilo said:

Can I use WBPP? Do I just load them in with the flats? Or put them in as bias?

I'm not familiar with particular PI scripts, so we should really wait for someone to answer that one.

Flat darks should be "darks for flats" - master flat dark created by stacking and then subtracted from flats prior to their stacking (same workflow as with regular subs where you subtract regular darks).

[AndyThilo]

Ok so I processed again using flats and flat darks. I used WBPP which according to someone on the PI forum I add the flat darks in with the darks. Carried out the same exact dynamic background extraction and autostretch. So it seems my issue all along was just really bad darks! @vlaiv you were 100% right. Thank you for all your help :). Seems my flat panel works just fine. I can't see much difference between flats and no flats, although the background noise looks a little cleaner with flats. I won't know for sure until I try a full processing session on both for full comparison.

Below then final image comparisons.

Old Darks (left) vs New Darks (right)

 

Old Darks with Flats (left unstretched, right DBE + Auto Stretch)

 

Old Darks NO flats (left unstretched, right DBE + Auto Stretch)

 

New Darks NO Flats  (left stretched, right DBE + Auto Stretch)

 

Finally New Darks with Original Flats + Dark Flats ((left stretched, right DBE + Auto Stretch)

[AndyThilo]

Conclusion, there is NOTHING wrong with my flats LOL. It was 100% the darks. The new darks with flats and dark flats produce a clean, clear final image. Not a massive improvement over the new darks without flats, but the background is cleaner and more uniform.