Hello
I think this is M22 in Sag? Taken with the Canon 40D at ISO400, it is a single, 600 second exposure through the Mewlon 180 F12 with x0.8 Flattener/Reducer at an effective fl of 1728mm, at F9.6.
There are a few things that are ‘wrong” with this image; amp glow in the top left hand corner, a little noisy due to it being just a single frame, some coma at the edges despite the x0.8FR and evidence of star elongation (flexure?), although this is less noticeable after the full 3888x2592 frame has been re-sampled down to 1024x680.
Usually, when using the ST7, CCDSoft and The Sky 6 Pro, the target details are written to the header of the FITs file but when using the Canon 40D, I’ll have to start writing details down about each target, so pardon my uncertainty.
Auto guided using a WO 66mm F6 Petzval and Orion Star Shooter (old model).
Cheers
Dennis