m101 (150sx16) C14 EdgeHD+hyperstar, EOS 60Da

[mmnb]

Finally have my hyperstar setup working. My stars suffer from some eccentricity, hopefully will be resolved after tuning collimation.  I also had some backlash in my focusing that must've affected things.

Not sure how I did here.  After calibration and PCC, mostly did some very gentle denoising, deconv, stretching and really just bumped saturation curve.  Other images have better hue contrast between the core and arms, but somehow this looks ok to me.  I noticed a bad blue cast after integration, I fixed with LinearFit.  Not sure how that happened (blue was weaker in flats?) so I don't think I lost any color contrast but a little worried since MaximDL's RAW Color images (automatically debayered, balanced) seem to suggest I would see more.

Would love any constructive crit. 500MB linear xsif after drizzle int and PCC:
https://drive.google.com/open?id=1x3L7CZ7NfR-RFOF9XeV58pQB7R8zwcdr

[mmnb]

Too much green in the first one. Nudged G and B curves, just a bit brighter too.

[Greg Schwimer]

You can solve the green problem by using SCNR at default settings while still linear.

[Juan Conejero]

The problem here is too few reference stars with the default automatic magnitude selection of PCC. If you increase the limit magnitude parameter to 15 (photometry parameters section) the result is correct color wise:


Click on the image for a full-size version.

Always watch the white balance function graphs. If the set of measured stars is small and scattered, you may need to force the use of more reference stars to compute significant white balance functions.

[Greg Schwimer]

Juan,

Good information. This has me wondering - will running PCC a second time end up with the same correct result as if it was run with adequate stars the first time. Put another way, is the result of the second PCC run influenced at all by the first run? I'm thinking not but it would be good to understand.

- Greg

[mmnb]

Juan,
Great info. I did notice that the lines in the PCC graphs were somehow un-compelling fits.  Thank you for taking the time to look at the image and articulate this important advice.