Hemisphere:  Northern  ·  Constellation: Draco (Dra)  ·  Contains:  NGC 4236
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NGC 4236 Galaxy in Draco, 


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NGC 4236 Galaxy in Draco

Getting plate-solving status, please wait...
NGC 4236 Galaxy in Draco, 


Powered byPixInsight

NGC 4236 Galaxy in Draco

Technical card

Imaging telescopes or lenses: Orion 8 Inch Newtonian Astrograph f/3.9

Imaging cameras: ZWO ASI071MC PRO CMOS OSC

Mounts: Orion Azeq Atlas pro

Guiding telescopes or lenses: ASTRO TECH AT66ED Guiding

Guiding cameras: Orion Starshoot Autoguider

Focal reducers: Baader MPCC Mark III Multi-Purpose Coma Corrector

Software: PixInsight  ·  Stark Labs pHD guiding PHD2  ·  EQMOD, Stellarium, Stellarium Scope, PHD, Backyard EOS, Astro Tortilla Nebulosity 4

Filters: Zwo Filter Drawer  ·  Optolong UV-IR

Dates:March 16, 2021March 18, 2021

Optolong L-eXtreme 2": 48x300" (4h) (gain: 90.00) -10C
Optolong UV-IR: 225x120" (7h 30') (gain: 90.00) -10C

Integration: 11h 30'

Darks: 30

Flats: 20

Bias: 50

Avg. Moon age: 3.71 days

Avg. Moon phase: 15.45%

Bortle Dark-Sky Scale: 8.00

Mean SQM: 18.48

RA center: 12h16m54s.22

DEC center: +69°2727.7

Pixel scale: 1.225 arcsec/pixel

Orientation: 41.576 degrees

Field radius: 0.587 degrees

More info:Open 

Resolution: 2133x2713

Locations: Home backyard red turning white zone Bortle 8, Gilbert, Az, United States

Data source: Backyard


NGC is a beautiful Galaxy in Draco. It lies 12 million light years away.

I learned something new this project... When using a Reflector type Telescope, and imaging on both sides of the meridian, the diffraction spikes can be a bit miss-matched after registration of the files. I remember reading about this in the past. I guess it must be the first time I imaged on both sides of the meridian using this Telescope.

After opening my Integrated Stack , it was a bit disappointing thinking I was going to have to use half of the subs.

What I ended up doing is integrating only the half that were on the East side of the meridian. This was to be used for only the stars.. Because it had the nice four diffraction spike pattern.

Then I used all of the subs to bring out more of the galaxy signal. I ended up using Starnett to remove these funky looking stars ( with the miss- matched diffraction spikes). Brightened up the Galaxy on this starless image. Then added it to the image with the good stars using Pixel math.

Then continued to process normally. I really enjoyed figuring out a way to make it work without throwing out half of the subs!



  • NGC 4236 Galaxy in Draco, 


  • Final
    NGC 4236 Galaxy in Draco, 




Description: 4 hours of additional data using the L-extreme filter.

Uploaded: ...

Sky plot

Sky plot


NGC 4236 Galaxy in Draco,