I finally had a chance to get back out and try some different backfocus settings and but still not able to get start to improve their shapes.
I had tried to 57.4mm backfocus but still see the same pattern the bottom left hand side of the stars are elongated pointing to the bottom left corner which would indicate not enough backfocus. I tried 59mm and still had the same issue. I was did not have enough threads in the flattener to add more delrin spacers so tried something drastic which was to add a 5mm spacer to try 60mm in total backfocus which did not produce much change.
I then went back to my original backfocus 56mm and took some shots to get myself back to a starting place again.I downloaded the trial version of CCD inspector and ran pics through the curvature and 3d plot analysis.
Looks like the direction of curvature is in the direction where i have the elongation of stars in the bottom left hand side of the image( of course with a completely untrained eye using CCDI ).
Any thoughts on the amount of curvature - indicated as 18.2% and tilt of 11% roughly in the direction of elongated star? Is this a small amount or is this a substantial value
I will try to run some more tests again tonight with different BF amounts to see what happens.
Edited by flyingg103, 17 November 2019 - 02:00 PM.