I tried imaging M61 a week ago, in order to capture SN2020jfo, but had problems with my tracking. The final composite image in Envisage looked unusually angular, which I put down to being a stacking artefact.
After seeing lovely images posted by accomplished astrophotographers, I tried again...with a similar result! Tracking was definitely better, but I had to remove quite a few hot pixels, masquerading as cosmic ray hits, from this 55m exposure made up of 5m subs. Imaging at native f10 is always challenging!
SN2020jfo is clearly visible, which I have marked in my 'upside down' image - I need a longer cable so I can reposition my camera, or to remember to rotate the final image in Startools. The supernova is bright, and may become visible in my 8" SCT; it follows in the footsteps of 8 previous recorded stellar explosions.
Back to those angular inner arms, in this barred spiral galaxy, which lies 52m LY from us in the Virgo super-cluster. This morphology is described as SAB in Hubble's nomenclature, although the literature seems to vary on this. An interesting article describes a second faint bar perpendicular to the first in the very active core making it double-barred [
https://www.calvin.edu...]; perhaps this explains the angularity?
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