Hemisphere:  Northern  ·  Constellation: Ursa Major (UMa)  ·  Contains:  Bode's Galaxy  ·  Cigar Galaxy  ·  ES UMa  ·  M 81  ·  M 82  ·  NGC 3031  ·  NGC 3034  ·  PGC2726822  ·  PGC2728713  ·  PGC2728721  ·  PGC2730379  ·  PGC2730409  ·  PGC2730709  ·  PGC2731294  ·  PGC2732102  ·  PGC2732338  ·  PGC2732797  ·  PGC2733060  ·  PGC28225  ·  PGC28505  ·  PGC28529  ·  PGC28757  ·  PGC28848  ·  PGC3086325  ·  PGC3097961
Getting plate-solving status, please wait...
M81 and M82 - Bode's Nebula and Cigar Galaxy, 



    
        

            Monkeybird747
Powered byPixInsight

M81 and M82 - Bode's Nebula and Cigar Galaxy

Getting plate-solving status, please wait...
M81 and M82 - Bode's Nebula and Cigar Galaxy, 



    
        

            Monkeybird747
Powered byPixInsight

M81 and M82 - Bode's Nebula and Cigar Galaxy

Technical card

Imaging telescopes or lenses: AG Optical 12.5" iDK

Imaging cameras: FLI PL16803

Mounts: Astro-Physics 1100 GTO

Guiding cameras: Starlight Xpress Ultrastar

Software: CCDWare PemPro  ·  PHD Labs PHD 2 Guiding  ·  SharpCap  ·  Starkeeper Software Voyager  ·  Pixinsight

Filters: Chroma Ha 3nm 50mm Square  ·  Chroma Blue 50mm Square  ·  Chroma Green 50mm Square  ·  Chroma Red 50mm Square


Dates:March 4, 2021

Frames:
Chroma Blue 50mm Square: 16x600" (2h 40') bin 1x1
Chroma Green 50mm Square: 18x600" (3h) bin 1x1
Chroma Ha 3nm 50mm Square: 28x900" (7h) bin 1x1
Chroma Red 50mm Square: 15x600" (2h 30') -35C bin 1x1

Integration: 15h 10'

Darks: 16

Flats: 20

Bias: 150

Avg. Moon age: 20.45 days

Avg. Moon phase: 67.63%

Bortle Dark-Sky Scale: 7.00

Mean SQM: 19.00


Astrometry.net job: 4303028

RA center: 9h 55' 53"

DEC center: +69° 20' 28"

Pixel scale: 0.870 arcsec/pixel

Orientation: -135.300 degrees

Field radius: 0.687 degrees


Resolution: 4015x4027

Data source: Backyard

Description

This was my galaxy season tester. I wanted to see how well I'd be able to image with the 12.5" iDK from my red transition zone (sqm 19.0). The sky conditions make RGB imaging problematic from my back yard. The gradients are fairly trivial to deal with, but the total integration time needed from my skies for RGB is what interests me. I think for this image to meet my goals I would easily need 5x the integration. Given that this is a bright target, that does not bode well (pun intended) for smaller, more faint galaxies this season. Still, it won't stop me from trying! I only ended up with 12 or so hours of RGB data, and no luminance. I sold the camera halfway through the project, so had to stack up what I had. This was also during about 75% moon, so not too bad given the conditions and short integration.

Blending the Ha data gave me fits. I discovered if I blended it early in the linear phase that it was wrecking color calibration and balance. I ended up waiting until near the end and blending the NBRGBCombination in PI during the non-linear phase. This worked much better for me. I don't do a lot of HaRGB, so this was another good tester. I don't really count the Ha towards the total integration time, since only small bits of the Ha data were used to supplement the red channel.

Comments

Sky plot

Sky plot

Histogram

M81 and M82 - Bode's Nebula and Cigar Galaxy, 



    
        

            Monkeybird747