Nightscapes & Deep Sky Colors

Astrophotography Brian A. Morganti

M51 Whirlpool Galaxy

Canes Venatici

100% crop resolution view of Whirlpool Galaxy below

The much larger of the two galaxies in this image is M51, commonly referred to as the Whirlpool Galaxy.  It is interacting with its companion galaxy NGC 5195, the smaller galaxy to the left (north) in this image.  M51 shines at magnitude 8.4, is a little over 10 arc minutes in visual size and is located about 30 million light years from Earth.  The actual size of the of the galaxy is estimated to have a radius of 43,000 light years. The "Whirlpool" is one of the most popular objects to be observed in the night sky by amateur astronomers, and it can even be glimpsed with binoculars under reasonably dark skies.   

A closer look at the top image will reveal at least two faint distant galaxies in the upper right quadrant of the image.


  • Date & Location:  April 1st & 21st, 2014 - StarEffects Observatory - Bernville, PA

  • Weather:  Light Breeze on 1st, Calm on 21st, Temperature average in high 30's F both mornings.

  • Sky Conditions:  Clear with  above average transparency on both nights.

  • SQM-L:  20.45 start - 20.11 finish on 1st (twilight), 20:46 start - 20:24 finish on 21st (moonrise).  Peak 20:55

  • Optics:  TeleVue NP101is Refractor @ 810mm f8.1 with 1.5x extender.

  • Filter:  Hutech IDAS-LPS (Light Pollution Suppression)

  • Mount:  AstroPhysics AP900GTO

  • Guiding:  Orion SSAG @5 seconds exposures.

  • Camera:  Canon T1i (500d) Hap Griffin modified - Baader UV/IR

  • Exposure:  23 - 10 minute subs  @ ISO800 -  (230 minutes) 3 hours 50 minutes total exposure time.

  • Calibration Frames:  12 Darks & Bias, 10 Field Flats & 10 Dark Flats w/Alnitak Flat Man -- Custom White Balance

  • Processing:  Images Plus 5.75a, PS CS6, GradientXTerminator, NIK filter tools 

  • Comments:  First time utilizing dark flats, and my first time imaging this target.   


Astrophotography  -  Nightscapes & Deep Sky Colors