Hemisphere:  Northern  ·  Constellation: Cygnus (Cyg)  ·  Contains:  Crescent Nebula  ·  NGC 6888
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NGC 6888 - Crescent Nebula - Jul 2021 - Ha BW, 



    
        

            Martin Junius
NGC 6888 - Crescent Nebula - Jul 2021 - Ha BW
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NGC 6888 - Crescent Nebula - Jul 2021 - Ha BW

Getting plate-solving status, please wait...
NGC 6888 - Crescent Nebula - Jul 2021 - Ha BW, 



    
        

            Martin Junius
NGC 6888 - Crescent Nebula - Jul 2021 - Ha BW
Powered byPixInsight

NGC 6888 - Crescent Nebula - Jul 2021 - Ha BW

Acquisition details

Dates:
July 17, 2021 ·  July 18, 2021
Frames:
Optolong H-Alpha 36mm 7nm: 19×600(3h 10′) (gain: 56.00) -5°C bin 1×1
Integration:
3h 10′
Darks:
20
Flats:
20
Bias:
50
Avg. Moon age:
8.00 days
Avg. Moon phase:
56.47%
Bortle Dark-Sky Scale:
5.00
Mean SQM:
19.85
Temperature:
17.00

Basic astrometry details

Astrometry.net job: 5397302

RA center: 20h11m04s.8

DEC center: +39°0028

Pixel scale: 1.402 arcsec/pixel

Orientation: 90.814 degrees

Field radius: 1.405 degrees

Resolution: 6077x3896

File size: 12.7 MB

Locations: Dellbrück, Köln, NW, Germany

Data source: Backyard

Description

Still a bit of a fight with the new setup ...

It seems that the Optolong filters and the Esprit 100 flattener don't work that well together. For now, I reversed the filters in the filterwheel, i.e. the more reflective side towards the camera, not the scope (the later the normal setup), which seems to mitigate some reflections from bright stars outside the frame, e.g. here near-by Sadr.

And then the CFW3M-US filter wheel gets stuck from time to time ... :-(

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NGC 6888 - Crescent Nebula - Jul 2021 - Ha BW, 



    
        

            Martin Junius