Hickson44

[Graham Darke]

Was out imaging from a nice dark site last night SQM reading of 21.41. This was a quick capture while I waited for M13 to rise. 10x180s and 5x300s stacked in DSS and processed in StarTools.

TEC140 and ASI071MC-Pro Camera at 0 degrees C. 

[kirkster501]

Very nice.  Nice colours and framing.  I think you have slightly over-clipped the black point - to reduce noise or to eliminate a gradient?  A bit of noise is OK.

[Graham Darke]

Not sure how black point adjustment works in StarTools. It always seems to produce a black background. 

[Clarkey]

2 hours ago, Graham Darke said:

Not sure how black point adjustment works in StarTools. It always seems to produce a black background. 

One of problems I have with ST is that I never get a black background! I seem to get lots of noise instead.... Despite changing settings and watching Ivo's videos I never get clean results. Lots of detail, but much noisier than any other processing.

Nice image though. I wish I could get this detail in such a short time.

[Avocette]

3 hours ago, kirkster501 said:

Very nice.  Nice colours and framing.  I think you have slightly over-clipped the black point - to reduce noise or to eliminate a gradient?  A bit of noise is OK.

I just downloaded the image and at least in GIMP the histogram doesn’t show any black level clipping from my perspective (well the 0 brightness pixel count is 191 out of a total of 3724225).

Edited April 10, 2021 by Avocette

[CCD Imager]

I like this image, a lovely cluster of galaxies with interesting detail and well captured.

The background does appear quite dark and I had a look in Photoshop. Using the colour sampling tool, levels are about 5, so although not strictly clipped, an optimum value should be around 20-30 giving a more natural appearance, after all nobody's skies are truely black..

I havent used Star tools, but it might be worth speaking to the author

Adrian

[Graham Darke]

I had another go at this one. The background is still very dark but I always find that with StarTools. This one is a bit noisier but I think I like the colour of this one better. I think I deliberately throttled the development (stretching) on the first one to prevent a satellite trail from showing up. I've restacked the subs in DSS using Kappa-Sigma Clipping and its done a better job of removing it.