Sh2-157 Lobster Claw Region - Includes NGC 7538, NGC 7635, M52, and Sh2-155 to name a few!

The Lobster Claw (Sh2-152), Cave (Sh2-152), Northern Lagoon (NGC 7538), Bubble (7635), and M52 all in the same field of view. How cool is that! This region of space on the border of Cassiopeia and Cepheus is loaded with gas dust and stars. I have listed the popular deep sky objects but many more small bright emission nebulae and dark nebulae are found in this image. I have imaged some of these such as M52, the Bubble Nebula, and the Cave Nebula individually before but this is the first for the Lobster Claw and Northern Lagoon. The Lobster Claw is a bright emission nebula located about ~11,000 light-years away in Cassiopeia where as the Bubble and Cave are closer at ~7100 and ~2400 ly away respectively.

All in all, I am quite pleased with the result and it took forever to process as I did a few new processing techniques which I will start incorporating into my routine, hopefully it will speed up. Although the processed image here was made from 15.9 hrs. of total exposure with the NBZ filter, I actually captured ~37 hours (449 x 300s) of data. You might think I am depressed about trashing ~20 hrs., but I began capturing this when the moon was out and was prepared to make an image with just that data. However, after I finished the first ~20 hrs. with the moon out, the clear weather returned when the moon went away so I started collecting again and the raw exposures looked noticeably better. The average ADU (brightness) was much lower without the moon. When I used the subframe selector in PI it was clear that frames without the moon were much superior. For example, the maximum number of stars detected was 2000 when the moon was out, meanwhile without the moon 5000 - 9000 stars were detected. One of the reasons for collecting so much data is so you can select the best that is possible so by that standard, not using the inferior data was a success.

So the new processing stuff was thanks to Mike Cranfield and Jerryyyyy, Bill Blanshan, Russell Croman. First I used Generalised Hyperbolic Stretch (GHS) which is a PixInsight script by Mike Cranfield which among other things can bring out faint detail much better than other methods I have used before. I also used Bill Blashan's Star Reduction and Color Masks Processes for PI. Lastly, I used NoiseXTerminator from Russall Cromin. I have been using Topaz Denoise but this seems to give a better reduction across the entire image. Topaz still works wonders though so I may use it as a secondary reduction in Photoshop.

  

Sh2-157 Lobster Claw Region - Includes NGC 7538, NGC 7635, M52, and Sh2-155!

Dates: 10-9-22, 10-10-22, 10-11-22, 10-12-22, 10-15-22, 10-16-22, 10-17-22, 10-19-22, 10-20-22, 10-21-22
Camera: ZWO ASI2600MC-Pro
Telescope: Canon EF 200mm f/2.8L II USM Lens
Barlow: None
Focal Length: 200mm
f/4 with stepdown rings
Focal Reducer: None
Mount: Orion Atlas Pro
Filter Wheel/Drawer: ZWO EOS Filter Drawer
Filter: IDAS Nebula Booster NBZ Filter
Focuser: None
Autoguiding: ASI120 Mini attached to a ZWO Mini 30/120mm Guidescope
Exposure: 191 x 300
Gain: 100
Sensor Temp: -10 C
Processing: ASIAIR Pro, PixInsight, Photoshop, StarXTerminator, NoiseXTerminator, GHS.
Power: BINZET AC to DC 12V 10A 120W Power Supply

https://www.instagram.com/astroquest1/
http://astroquest1.blogspot.com/
https://www.astrobin.com/users/kurtzepp/collections/
http://youtube.com/c/AstroQuest1