alberio Loc: Casa Grande AZ

This is my interpretation or crazy processing of this object. I used a Askar 120mm f7APO @f5.6 with a total 29 subs of mixed exposure times 15-30 sec each. The ISO was also varied from 800-1600 with one at 12,000. The camera was a Canon R6. No darks or flats, just stacked and processed in a really old version of Nebulosity and final tweeks in Topaz. I know the colors are a bit weird, but my grandaughter likes them. There are also strange artifacts I probably introduced with my aggressive stretching/processing. I'm not sure how to eliminate them.

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Retired CPO Loc: Travel full time in an RV

Looks very cool!

Railfan_Bill Loc: "Lost Wages", Nevada

Hey Alberio, could these noise be from the camera? You used the R6 on the other photo and got some strange noise patterns, too. These noise "streaks" are too coincidental to be random. Look at the pattern and the streaks fall into the same distance on the image. I hope I am making this clear. This may be caused by the camera sensor since it occurred on other posted photos, but not as prominent. just a thought. RFB

alberio Loc: Casa Grande AZ

Thanks Bill for the input, I'll see if I get the same type of squiggles on separate shots. You could be on to something. I think Ballard asked if I took any dark or flats, and that might help to reduce or eliminate these also. I admit my work flow is a bit unconventional and possibly too aggressive, trying to get too much out of the limited data I had. Post processing, stacking, converting from RAW toTiff to Fits could also be part of the problem. Thanks again for the suggestion. I'll see if I can pin it down to one source.

Ballard Loc: Grass Valley, California

Neat shot. There are some unusual strings of dots that appear in the image. I'm not sure what can cause this type of noise, do you see them in the individual frames? I would try some making some dark frames and see if they show up there, if so the dark frames would help reduce them.

alberio Loc: Casa Grande AZ

Yeah, I think my aggressive processing is the cause. I'll try some dark frames and see if that helps. I went out last night and set the camera to high ISO noise reduction and long exposure noise reduction. It cleaned up the images to where I don't see those artifacts. Next time I'll try taking some actual dark frames. Thanks for the help.

btrlvngthruchem

I second your granddaughter's opinion about the colors especially the contrasty red.

The odd groupings of white dot artifacts are interesting. Each group is identical with regard to the number and location of the dots relative to each other. The groupings however, appear to be completely random in their locations in the image. Since you were able to get rid of the artifacts using noise reduction through the camera, this suggests that a good set of dark calibration frames will solve the problem as previously mentioned.

Just as an FYI and FWIW, I saw something in your image that I saw in an image I was working on the other day. I noticed most of the smaller stars in my image exhibited a tear-drop shape. I went back through the original individual light frames and examined them more carefully than I had done prior to the original stacking. I found the smaller stars in several of lights were quite elongated, whereas the larger stars looked perfectly acceptable. It seems the larger stars camouflaged a tracking error in those bad lights. Once I removed the bad lights, the stars were all nice and round.

I have to say I'm so jealous of your dark skies, or access to them. Light pollution on the west coast of Florida is getting worse by the week with all the building going on.

alberio Loc: Casa Grande AZ

I believe you're right about the elongated stars. The mount I use is the Celestron Advanced VX, which is by no means a high end mount and it probably has some periodic error in the gears. It's still a pretty good mount within its limitations. I'll have to be more critical about the subs I select. I'm sure the use of dark frames and careful focusing will help the final image. Thanks for checking it out and for the input. I'm always willing to learn all the tricks.