Hemisphere:  Northern  ·  Constellation: Cancer (Cnc)  ·  Contains:  11.08  ·  38 Cnc  ·  39 Cnc  ·  40 Cnc  ·  41 eps Cnc  ·  42 Cnc  ·  5 Astraea  ·  Beehive  ·  Beehive cluster  ·  IC2388  ·  IC2390  ·  M 44  ·  M44  ·  NGC 2632  ·  NGC2624  ·  NGC2625  ·  NGC2637  ·  NGC2643  ·  Praesepe  ·  Praesepe Cluster
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Beehive Cluster M44, 



    
        

            matthew.maclean
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Beehive Cluster M44

Getting plate-solving status, please wait...
Beehive Cluster M44, 



    
        

            matthew.maclean
Powered byPixInsight

Beehive Cluster M44

Technical card

Imaging telescopes or lenses: William Optics GT81

Imaging cameras: Altair Astro Hypercam 269C Pro TEC

Mounts: iOptron CEM25p

Guiding cameras: Altair Astro GPCAM2 290M

Focal reducers: William Optics Flat 6Aiii

Software: Aries Productions Astro Pixel Precessor  ·  PixInsight 1.8

Filters: Baader Moon & Sky Filter 2"

Accessory: William Optics Right Angle Guide Scope 50mm


Dates:May 1, 2020

Frames: 24x160" (1h 4') (gain: 1200.00) -10C

Integration: 1h 4'

Darks: ~12

Flats: ~12

Bias: ~20

Avg. Moon age: 8.07 days

Avg. Moon phase: 57.25%

Bortle Dark-Sky Scale: 6.00


Astrometry.net job: 3489265

RA center: 8h 40' 7"

DEC center: +19° 46' 5"

Pixel scale: 1.770 arcsec/pixel

Orientation: 83.945 degrees

Field radius: 0.909 degrees


Resolution: 2958x2217

Data source: Backyard

Description

Open clusters, I know, not very exciting. This is a simple shot taken to do some more testing of the new 269C astro-camera and get a little data to learn a something about using PixInsight. A 2/3 moon was about 30-deg azimuth away from M44 during this shooting, so colors definitely suffered, but got a decent raw dataset to work with.

I set the gain a bit higher here to get a more balanced histogram from the new camera -- probably went a bit too far as the star centers are a bit saturated, but I now understand the boundaries much better, so a valuable lesson learned. I've also switched to shooting using SharpCap with the Altair cameras; among several benefits, as an engineer, I really like getting the raw histogram data from it and importing into Excel. It gives the actual counts obtained on 4096 bins (2^12) and made it quite understandable what I was getting on the bias, dark, and light frames.

Version A is processed with Astro Pixel Processor (my baseline process). Image integration is quite turn-key.

Version B is my attempt with PI. Integration seems a lot more difficult with PI. The main issue I had with it is trying to neutralize the flat frames which otherwise are heavy tinted toward the green channel because of the default (natural) white-balance of the camera. I did some very convoluted things to address that, so any suggestions are welcome. In the end, I got an integrated image with a background that is almost too clean, but it seemed to work at least.

I think Version A (APP) retained slightly better color contrast, Version B (PI) has maybe lower background noise and sharper stars. At this point, I'm more interested in images I learn something from than perfection, so this set goes into my gallery as record of how far I've come and how far I have to go.

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Revisions

  • Final
    Beehive Cluster M44, 



    
        

            matthew.maclean
    Original
  • Beehive Cluster M44, 



    
        

            matthew.maclean
    B

B

Description: PixInsight processed version

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Beehive Cluster M44, 



    
        

            matthew.maclean

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