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

Technical card

Imaging telescopes or lenses: Skywatcher Esprit 100ED APO Triplet

Imaging cameras: QHYCCD QHY268M

Mounts: Skywatcher AZ EQ6 GT

Guiding cameras: Lodestar X2

Focal reducers: Skywatcher Esprit 100 F5.5 flattener

Software: N.I.N.A. Nighttime Imaging 'N' Astronomy  ·  Adobe Photoshop Lightroom Classic  ·  Pleiades Astrophoto S.L. PixInsight 1.8 Ripley  ·  PHD2 Guiding  ·  Cartes du Ciel

Filters: Optolong H-Alpha 36mm 7nm


Dates:July 17, 2021July 18, 2021

Frames:Optolong H-Alpha 36mm 7nm: 19x600" (3h 10') (gain: 56.00) -5C bin 1x1

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: 4890720

RA center: 20h 11' 4"

DEC center: +39° 0' 28"

Pixel scale: 1.402 arcsec/pixel

Orientation: 90.814 degrees

Field radius: 1.405 degrees


Resolution: 6077x3896

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