Hemisphere:  Northern  ·  Constellation: Cancer (Cnc)  ·  Contains:  1 kap Leo  ·  10 mu. Cnc  ·  10.56  ·  10.86  ·  11.98  ·  12 Cnc  ·  12.36  ·  12.66  ·  12.89  ·  13 psi01 Cnc  ·  13.27  ·  13.29  ·  15 Cnc  ·  159 Aemilia  ·  16 zet01 Cnc  ·  16 zet02 Cnc  ·  17 bet Cnc  ·  18 chi Cnc  ·  19 lam Cnc  ·  2 ome Cnc  ·  20 d01 Cnc  ·  21 Cnc  ·  22 phi01 Cnc  ·  224 Oceana  ·  23 phi02 Cnc  ·  24 Cnc  ·  25 d02 Cnc  ·  27 Cnc  ·  28 Cnc  ·  29 Cnc  ·  And 255 more.
Cancer the Crab, 



    
        

            lefty7283
Powered byPixInsight

Cancer the Crab

Cancer the Crab, 



    
        

            lefty7283
Powered byPixInsight

Cancer the Crab

Technical card

Imaging telescopes or lenses: Tamron 17-50mm F2.8

Imaging cameras: ZWO ASI1600MM-Pro

Mounts: Orion Sirius EQ-G

Guiding telescopes or lenses: Agena 50mm Deluxe Straight-Through Finder / Guide Scope with Helical Focuser

Guiding cameras: ZWO ASI 120 MC

Software: Nighttime Imaging 'N' Astronomy  ·  PixInsight 1.8 Ripley PixInsight

Filters: Astronomik B 31 mm Type IIc  ·  Astronomik G 31 mm Type IIc  ·  Astronomik R 31 mm Type IIc  ·  Astronomik L 31mm Type IIc

Accessory: ZWO EFW 8 x 1.25″/31mm


Dates:Jan. 7, 2019

Frames:
Astronomik B 31 mm Type IIc: 7x180" (21') (gain: 139.00) -20C
Astronomik G 31 mm Type IIc: 7x180" (21') (gain: 139.00) -20C
Astronomik L 31mm Type IIc: 32x180" (1h 36') (gain: 139.00) -20C
Astronomik R 31 mm Type IIc: 7x180" (21') (gain: 139.00) -20C

Integration: 2h 39'

Darks: 30

Avg. Moon age: 1.29 days

Avg. Moon phase: 1.88%

Bortle Dark-Sky Scale: 3.00


RA center: 08h40m03s.682

DEC center: +19°5744.70

Pixel scale: 22.643 arcsec/pixel

Orientation: 91.539 degrees

Field radius: 16.844 degrees

More info:Open 


Resolution: 4293x3223

Locations: Deerlick Astronomy Village, Sharon, GA, United States

Data source: Traveller

Description

This was a secondary target to my Widefield Orion image. Because Orion hit the trees at 3am, I wanted to image another target with the remaining 3 hours of astro-dark. My reasoning for capturing this constellation specifically was that I wanted to image an entire constellation, but not have to change my lens focal length or rotate the camera sensor. The Cancer constellation won out over Bootes due to the M44 cluster being right in the middle. It appears the glass in front of the sensor dewed over, resulting in some weird star halos. [Due to the subjective nature of this hobby](https://i.imgur.com/TgX0m2d.png) I decided to keep the halos in since this is a stars only image. [Here is an annotated image highlighting the constellation lines and clusters](https://i.imgur.com/UeJh55c.jpg). Captured on the morning of January 7th, 2018 from the Deerlick Astronomy Village, a Bortle 3 Zone.



**Equipment:**

* Tamron 17-50mm f/2.8

* Orion Sirius EQ-G

* ZWO ASI1600MM-Pro

* ZWO EFW 8x1.25"/31mm

* Astronomik LRGB Filters- 31mm Mounted



* Agena 50mm Deluxe Straight-Through Guide Scope

* ZWO ASI-120MC for guiding

**Acquisition:** 2 hours 39 minutes (Camera at Unity Gain, -20°C) (Lens at 35mm f/5.6)

* L- 32x180" (1h 36m)

* R- 7x180" (21m)

* G- 7x180" (21m)

* B- 7x180" (21m)

* Darks- 30

**Capture Software:**

* EQMod mount control. Captured using [N.I.N.A.](https://bitbucket.org/Isbeorn/nina/overview) and PHD2 for guiding and dithering.

**[PixInsight Processing](https://i.imgur.com/JLMWInr.png):**

* BatchPreprocessing

* ImageIntegration

* DynamicCrop

* DynamicBackgroundExtraction

* **Lum**

* TVGDenoise

* MultiscaleMedianTransform

* ArcsinhStretch

* **RGB**

* LinearFit to green

* ChannelCombination

* AutomaticBackgroundExtraction

* PhotometricColorCalibration

* HSV Repair

* ColorCalibration

* ArcsinhStretch

* HistogramTransformation

* LRGBCombination with Luminance

* HistogramTransformation again

* ACDNR

* Several [Curve](https://i.imgur.com/bZ2PsWf.jpg)Transformations

* Annotation

Comments

Sky plot

Sky plot

Histogram

Cancer the Crab, 



    
        

            lefty7283