Hemisphere:  Northern  ·  Constellation: Ursa Major (UMa)  ·  Contains:  M 108  ·  M 97  ·  NGC 3556  ·  NGC 3587  ·  Owl Nebula
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M97/M108 - the 'owl and the pussy cat?', 



    
        

            Tom Gray
M97/M108 - the 'owl and the pussy cat?'
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M97/M108 - the 'owl and the pussy cat?'

Getting plate-solving status, please wait...
M97/M108 - the 'owl and the pussy cat?', 



    
        

            Tom Gray
M97/M108 - the 'owl and the pussy cat?'
Powered byPixInsight

M97/M108 - the 'owl and the pussy cat?'

Technical card

Imaging telescopes or lenses: William Optics Zenithstar II 80 ED

Imaging cameras: Meade DSI 3 Pro

Mounts: Meade LX6 premier with 'smartdrive'

Guiding telescopes or lenses: Meade 8x50mm Finder/Guider

Guiding cameras: Orion Starshoot autoguider

Focal reducers: Meade f3.3 focal reducer/field flattener Meade Focal reducer

Software: SiliconFields / Ivo Jager StarTools v1.6  ·  PHD2 Guiding V 2.6  ·  Penumbra (George Morimosato) v0.6  ·  Meade Envisage V4.10

Filters: Meade RGB-IR Cut 1.25"  ·  Meade LRGB 1.25"

Accessory: Homemade Dew Controller  ·  Homemade ST4 autoguider


Dates:Jan. 23, 2021

Frames:
Meade Blue Filter for CCD: 19x120" (38') bin 1x1
Meade Green Filter for CCD: 13x120" (26') bin 1x1
Optolong L-eNhance 1.25": 12x300" (1h) bin 1x1
Meade Red Filter for CCD: 26x120" (52') bin 1x1

Integration: 2h 56'

Darks: ~17

Flats: ~25

Avg. Moon age: 9.70 days

Avg. Moon phase: 73.71%

Bortle Dark-Sky Scale: 4.00

Temperature: -1.12


Basic astrometry details

Astrometry.net job: 4178824

RA center: 11h 13' 4"

DEC center: +55° 16' 44"

Pixel scale: 3.900 arcsec/pixel

Orientation: 180.404 degrees

Field radius: 0.932 degrees


Resolution: 1373x1036

Locations: Home 'observatory' (Bortle 5), Derbyshire, United Kingdom

Data source: Backyard

Description

M97 and M108 make an interesting pair - my rather ‘cartoonish’ owl looks on, to what might be best described as some form of ‘roadkill’! In truth, M97 is a planetary nebula, puffed off the central star (just visible between the eyes) around 8000 years ago, and expanding ~30km/s. M108 is a barred spiral galaxy, some 45m LY from earth, with a diameter over 100,000 LY. Very little detail, beyond some mottling is visible in my ‘squashed’ image.

Despite a promising start - an hour of data (5m subs) through my narrowband filter, was supplemented with RGB (120s subs) through increasing haze and cold. I have struggled again with excessive noise and gradients and the resultant data has been severely clipped to boost contrast.

Definitely not my best effort, but deserves to be recorded, if not shared.

Comments

Revisions

  • M97/M108 - the 'owl and the pussy cat?', 



    
        

            Tom Gray
    Original
  • Final
    M97/M108 - the 'owl and the pussy cat?', 



    
        

            Tom Gray
    B
  • M97/M108 - the 'owl and the pussy cat?', 



    
        

            Tom Gray
    C

B

Description: Processed in Nebulosity with non-linear transformation to darken background - I’m not sure this is any better.

Uploaded: ...

C

Description: My final effort, uses data from my NBF applied equally to G and B channels, but introducing more noise in the process. I expect my tri/quad band L-eNhance filter may be in part the cause of this. It is of course designed for use with OSC, and therefore introduces excessive, and noisy OIII data. One day I’ll get myself a set of individual narrowband filters...

Uploaded: ...

Sky plot

Sky plot

Histogram

M97/M108 - the 'owl and the pussy cat?', 



    
        

            Tom Gray