Canon EOS Rebel T7i 'modified-Hutech' using a 20mm Pentax Eyepiece for eyepiece-projection into an APM Flattener thru a 152mm A+M Refractor(OfficinaStellare) hoping to correct the 'flarring' but it didn't on M16 .. which 'solved' at 2500mmF/F . I then switched to the normal PrimeFocus with the APM Flattener and Rebel T7i and tried an un-guided 1xSidereal 'one-shot' color image at about 3:30amEDT early this morning and the 'collimating' I did with the Refractor Collimator might have helped the stars to the edges.. but this image is with the APM Flattener with it's original housing for just 'crop-factor' camera images , M27 was used and 'solved' at 1175mm F/L with only a Moon 'focus' done to it before the image was taken .x FITS is 'HfSz' then Bin3 .
Robert, To get good results, you need to simplify everything, and eliminate the number of optical devices and mechanical connections. In my opinion, the M16 image is terrible. Sorry for saying that. Is this APM flattener designed for your refractor ? The eyepiece projection adds distortions of the eyepiece.
