The pair of galaxies near the center is NGC 6285 (top) and NGC 6286 (bottom). The lower one has a distinct tidal trail below it, and a faint bridge to the upper galaxy is visible. Both sit around z=0.018.
The edge on galaxy is UGC 10641, and sits at a similar redshift to the pair at z=0.018, indicating that this is probobly a group of three gravitationally bound galaxies.
My field also included a galaxy cluster around 16h57m49s +58°46'55":
The brightest member, LEDA 2582489 has a reshift of around z=0.11, which puts it at a comoving distance of 1.5 Gly, way beyond the main target of the photo.
It looks like my guiding got messed up after the meridian flip, resulting in some annoying walking noise.
If the when the telescope is drifing, stacking will smear out the sensor's pattern noise into diagonal lines. This "walking noise" is visually distracting and messes with edge-preserving filters. Callibration frames help, but they don't remove it: some pixels are inherently noiser than others.
Normally, I avoid the problem by using a second camera to lock the scope's pointing to a nearby star and add ~10 px of random perterbation every 5 frames. This ensures the noise ends up evenly distributed in the final image.
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