returned to NGC 4559 (Halifax)

Tried to improve on my first attempt with Finest NGC 4559, a lovely canted spiral island universe in Coma. I imaged this with BGO back in 17 Dec '17 but noted banding in the image and donut artefacts. This run with BGO, with the repaired Apogee camera, looks better.

Luminance only, 60 seconds subexposures, 10 stacked shots. FITS Liberator, GIMP. North is up; east is left.

Smoother background, no noticeable artefacts. But gosh-darn, this is a tough one. The foreground stars are easy to blow out when trying to reveal the tantalising details in the core and spiral arms.

Proper processing would require removing the stars...