Sh2-171/NGC 7822 and NGC 7762
Sh2-171/NGC 7822 (lower right in photo) is a large emission nebula in the constellation Cepheus (Cep) and makes an interesting (and colorful!) narrowband subject since there is significant Ha, SII, and OIII emission. It also has many pillars created by stellar winds from nearby hot stars and many associated dark nebulae, all of which make it a great narrowband target to image and process.
The partial large loop of emission nebula on the left side of the photo is NGC 7762, often imaged with Sh2-171.
Capture Date: 10/23/23
Average Moon Illumination 65%
Askar 107PHQ w/ 0.7x reducer (fL = 524 mm)
ASI2600MM Pro (Monochrome camera)
ZWO 7-position 2” Electronic Filter Wheel (EFW)
ZWO AM5 mount with guiding via SV106 and ASI178MM
Antlia 3nm Narrowband H-alpha 2": 15×300″(1h 15′)
Antlia 3nm Narrowband Oxygen III 2": 12×300″(1h)
Antlia 3nm Narrowband Sulfur II 2": 15×300″(1h 15′)
Antlia V-Pro Blue 2": 10×120″(20′)
Antlia V-Pro Green 2": 10×120″(20′)
Antlia V-Pro Red 2": 10×120″(20′)
Total Integration: 4:30
All light frames calibrated with dark, flat, and bias frames
Pre- and post-processed in PixInsight
Additional post-processing in Photoshop for exposure adjustments and generation of reduced size jpeg
Nice image Greg! Glad you are getting some time with the skies and testing out some new equipment.
@terri This was actually a test of the 0.7x reducer for the 107PHQ. I didn't intend on getting much out of it besides examining the star distortion, but I was happy with the image despite only having a few hours on it. I remembered the stars being distorted last year when I tried the reducer so I wanted to test it again since there are few targets I'd like to use it with this fall. I think the stars are very presentable, though, and I don't see much distortion, so I was happy about that.
I also had a chance to test out Adam Block's 'Modifiers' technique to render the colors in the final image. That was pretty neat, and it worked very well. I wish I had just a thimble full of the knowledge and skill that guy has!