GHS vs. Masked Stretch + Arcsinh Stretch vs. HT + CT

Bruce Donzanti

I was curious, and finally had the time, to try and compare these 3 stretching approaches.  I was particularly interested in what I could do with GHS.  I've attached 3 images, one from each approach using M13 as my test subject.  I only had 4 hrs of data on a hot central Florida summer night.  In fact, my ASI6200MM camera could only get down to -5 vs. the normal -10 I usually use to image with it.  This was taken on a C11" EdgeHD @ f/10 (2800mm) using Chroma RGB filters and the Optolong LP filter, L-Pro since I am under Bortle 7 skies.  

I think the stars have a better in shape (less bloated) using GHS but the color is still a bit pale vs. MS + AS, even after I did an additional color punch on the GSH image.  Playing with GSH after watching D. Payne's and M. Cranfield's video multiple times, I am learning that: 1) it does have a steep learning curve and 2) the various parameters you can manipulate are very sensitive to minor adjustments. I tried many combinations and permutations of the various settings in the GHS tool but I am far from really mastering it.  

I am mainly posting this to see if others have tried it compared it to the more traditional methods and what your experience has been using it.

Bruce

jeffrey merrill

Hi:  I'm curious if anyone else has tried this as well.  To be honest I had to search GHS - generalized hyperbolic stretch script to learn what it was.  

I agree that your GHS version posted seems to have less star bloat..and honestly I dislike what ArcSinh Stretch does to star colors (bland solid color even at center) and prefer your GHS version as it maintained the central brightness of the blue stars.

Adam: also wondering if you have tinkered with this script?

jeff

Bruce Donzanti

Thanks for the feedback, Jeff.  

A few folks I know have been tinkering with this script, with mixed results, in my opinion.  Hopefully, Adam will weigh in on this topic.