Picked up this lens second hand for $400 off of gum tree. Turned out to be a ripper! ZERO CA, sharp stars. The only "issue" is the coma at the edges of the field due to the full frame. I'll try stepping it down a few F stops to see if it helps but I'd prefer to image at wide open if possible. I sort of just pointed it roughly at SCP and let it go. I could get 30 seconds without significant trailing and did about 160 or so subs which were cut down to 100 or so after I realised the last 60 were useless due to dew.
Bonus Rosette from ED72 QHY8L AZ GTe EQ mount. Got this set up purring now. guiding successfully.
Astrobin Links:
M42 & Horsehead
Rosette
