Last night I noted the guide star was very small and tight, the best seeing Ive seen in some time, from my backyard in Newcastle. I was doing NGC 55, manually guiding my 1986 vintage 10 inch Newtonian.
Image is 6 x 15 minutes ISO 400. No filters.
Some of the bright stars aren't 100% round, I think its the full thickness mirror still a bit warm as the night air cools down, setting up a bit of an air current. Its a Pyrex Sutching mirror so no question of its quality
An off axis guider that "looks" from behind a coma corrector is just so nice. Round, not comatic guide stars, and the plastic worm wheel surprisingly well tracking, with its regular and easily correctable periodic error allowing me to keep the guide star sitting nicely on the virtual reticle.
Im investigating using a 2x converter to double the magnification and focal length, for those smaller objects where there is so much wasted space in the full frame camera view.
The EOS Ra is just great to focus, with 30x live view. Helped by the fact I disassembled the focuser, degreased it and coated the contacting surfaces with Teflon based gear oil, now it feels so smooth to focus and with absolutely no play at all.
The view shown is a full resolution crop, and a larger view is here
https://www.astrobin.com/611z1k/0/
calibrated and processed with freeware IRIS and finished in Photoshop.
Scott