Comet Lemmon Data Up for Review – Banding / Pixelation Issue

I’m returning to DSO astrophotography after nearly eight years away, and needless to say, my PixInsight skills needed quite a bit of refreshing.

I’m using the same setup as before, but I’ve switched to a Sony A7 IV DSLR for imaging because of its versatility for both deep-sky and wide-field work. Previously, I photographed with a Canon 60Da and never really had any issues processing the data in PixInsight when using proper calibration files.

Last week, I photographed Comet Lemmon and ran into trouble processing the data in PixInsight. I captured 85 light frames (30 s each) along with darks, flats, and bias frames. After integration, the image looked fine, but as soon as I applied DBE or any background neutralisation, it turned into a pixelated mess with banding and generally poor results.

I’m trying to figure out whether the issue lies with my PixInsight skills or the DSLR itself. I had a similar problem when stacking some wide-field shots of the galactic core. Comet Lemmon’s session was under bright moonlight (about 84 %), with the ISO set to 800.

If anyone’s willing to take a look at the data or work on a subframe, I’d love to know whether this is simply user error or an actual data problem.

Original and calibrated/integrated files are available.
I can share a Google Drive link via private message.

Any help would be greatly appreciated!