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Astrophotography

Several Clar nights and a LOT of images
Jeffrey McClure
12/21/2023 6:53 PM

I have been deficient in not posting my recent images here, but in my defense, I am currently sleep deprived from doing a Marathon run of imaging and processing. I am gradually posting them on Astrobin (Jeff McClure). Here are some you will recognize with more to follow.


The Cone image (NGC 2264) is, I think, unique. I shrunk the foreground stars to reveal the sculped structure of that huge, mostly dark nebula. All my recent images have been shot using my new Askar V scope in its 60mm reduced configuration (270mm f/l). The NGC 2264 image was the result of three nights and about 15 hours of 300 sec. exposures in H-alpha, S-II, and O-III. It was my first venture into Mosaic imaging. The initial image was a whopping 1 gagabyte in size! I had to remove my OAG from the ASI2600MM-Pro to get the sensor close enough to focus with the reducer, so I am now using the Askar 36mm 120mm f/l guidescope.

abrickhouse
12/21/2023 7:14 PM
Hi Jeff. These are great images from your set up. I like the Horsehead very much in the wide field shot. Lots of good color and sharp image. The Cone really looks different with most of the stars removed. It is a super sharp shot. The scope is very sharp. 

What program are you using to remove or minimize the stars? I am using an AI program from RC-astro (from Austin) that does a great job running on Photoshop. 

In the past, I have not run imaging beyond about 3 hours of data but I am only running about 15 subs of 5 minutes for most of the bright objects with the QHY 168. I had to take a lot more images when I used the AT 72 mm refractor. 

I really have become a great fan of the QHY 168 since I figured out how to run it on SharpCap 4+ software. If you keep the light curve matched there is little adjustment required in the first processing. Of course,  that must be tracked carefully as the curve changes some by altitude and exposure time. (diffraction / absorption)

Aubrey



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Jeffrey McClure
12/22/2023 3:42 PM
Aubrey,
I do capture with the ASIAIR+ and while it will do stacking, I don't use it for that. I run all of the mosaic and grunt work as well as star reduction (it will not completely extinguish the stars) in Astro Pixel Processor, then shift to Lightroom Classic to clean up and do fine color adjustments. I have been considering relearning Photoshop to get the Star Exterminator plugin. 

abrickhouse
12/22/2023 3:50 PM
If you decide to go to Photoshop you can get the star elimination and you can buy some action software for astronomy that eliminates a lot of the grunt work. I am finding that the cmos cameras are much quieter and a lot of the noise work is minimal. Your equipment is working well for you.

Jeffrey McClure
12/22/2023 8:03 PM
Aubrey,
Thanks for the tip! I don't have to do biases with this camera as there is virtually no amp glow. I generally only need a Bad Pixel Map and flats and often don't even need flats as the software does a great job of detecting both light pollution and gradients. I just want to be able to totally remove stars and Astro Pixel Processor, although otherwise a dream, leaves tiny dots that look like noise. 
Jeff

abrickhouse
12/22/2023 8:13 PM
Yes I very seldom use flats. You really don't need bias calibration as the dark captures the total noise of the set exposure. Russell Crows' AI implementation takes out all but a really large star and then it is muted so that when you recombine the three images it goes back to the original state.

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