Don't you always have to test new stuff on M42 if its available to shoot? Its like a rule or something, no? LoL!

This is a GSO coma corrector test with an 8" F/4 GSO Newt. I'm still waiting on some parts needed to get this thing to mesh with my scope, so it was not the real test of the final configuration. This particular corrector has to be at a nominal 75mm (+/- 10mm) distance from the camera's focal plane to work right. Since I didn't have the T-ring spacer kit I ordered yet I used this old Lumicon Deep Sky filter in a T-thread mount that was about 15mm. Let's just say it has issues. Plus, my focuser didn't have enough back focus, so I had to hang some of the assembly out of the focuser far enough to reach infinity focus. I didn't foresee that problem. Maybe a 2" parfocal ring will help in this case, since it isn't much that I am short and the barrel of this thing is really long.

BTW, this unit increases the focal length and f/ratio about 1.1 times or more. With the help of IRIS, I calculated it went from 800-something mm to exactly 915mm focal length.

I left the IDAS-LPS drop-in filter I usually use installed and used both it and the Lumicon. That gave some weird color shift results. But, boy - it really cuts out lots of LP! It was too dim at my usual 3 minutes & ISO 1600 settings, so I used ISO 3200 instead. I was lucky it was 37 degrees F at the time, so i could get away with that. I'm still trying to work out guiding longer than 3 minute with this setup (50mm finder and SSAG.)

Unfortunately, since I had to rig this installation, I couldn't get the camera to sit perfectly square in the focuser and collimation suffered as a result. Star shapes were screwy even though I had carefully collimated before shooting. The guiding wasn't too hot, either. Because of the above, I had to do lots of star repairs for this display image.

And as you can see, 3 minutes at ISO 3200 nuked the core really hard and it is grossly over-exposed. Oh, well... it was just a test image, anyway. :-)