Messier 45 The Pleiades Cluster

M45, or commonly known as the Pleiades, is arguably one of the prettiest Messier objects. The Pleiades are also mythologically known as the Seven Sisters: Sterope, Merope, Electra, Maia, Taygeta, Celaeno, and Alcyone. Their parents are the stars Atlas and Pleione. The Subaru is the Japanese name for the Pleiades or the “Seven Sisters” (one of whom tradition says is invisible – hence only six stars in the Subaru logo), which inspired the logo.

The Pleiades might look like a constellation; however, it is an asterism. An asterism is a commonly recognized group or pattern of stars that is not a constellation. The Pleiades are easy to spot with the naked eye. The Pleiades can be seen easily even in a very light polluted Bortle 9 sky.

The best way to find Pleaides is by finding Orion’s belt and following the belt up to Aldebaran and then follow that line to a small cluster of stars. You have arrived at the Pleiades.

The Pleiades is an open cluster of stars, and it’s a reflection nebula formed at a young age of 100 million years ago. The Pleiades is about 391 million light-years away. The blue nebulosity around the cluster is made from dust particles reflected off the nearby stars’ light.

The area of the sky that is photographedThe area of the sky that is photographed.

Messier 45

I took this target at Voorhees State Park, in NJ. I had trouble getting the camera getting down to -20, so I had it down to -10c during the entire night. I had switched to B33 (Horsehead Nebula) after this target.

Processing Info

I took 27 frames at 300 seconds each. I had to throw away five frames. I stacked the
22 light frames along with 50 dark and 60 flat frames in PixInsight.

The following processes were performed in PixInsight:

  • Dynamic Crop
  • Dynamic Background Extraction
  • Background Neutralization
  • Color Calibration
  • Photometric Color Calibration
  • MultiScale Linear Transform
  • Histogram Transformation
  • LRGBCombination
  • Curves Transformation (X2 with a range mask. Inverted mask for the background and then non inverted for the target)
  • Color Saturation (X2 with a range mask. Inverted mask for the background and then non inverted for the target)
  • SCNR
  • Morphological Transformation (Generated StarMask using default settings)
  • Local Histogram Equalization (Performed with a range mask)

Once I found what I liked, I saved the files and went to Photoshop. I played around with the levels, vibrance, and saturation a bit. I then ran Topaz AI DeNoise. This is an amazing plugin that works like magic.

Acquisition Data

  • Telescope: Explore Scientific ED127 f7.5 Air-Spaced Triplet Apochromatic Refractor
  • Camera: ZWO ASI2600MC Pro
  • Guide Scope: Orion ST80
  • Guide Camera: ZWO ASI290MM Mini. Dithering every image at 1 pixel each time.
  • Mount: iOptron CEM60
  • Software: NINA for image acquisition. PixInsight used for stacking and editing. Imported to Photoshop for final touchup and watermarking.
  • Other Accessories: AstroZap Dew Heater, Starizona Apex ED 0.65x L
    Reducer/Flattener, MoonLite CFL 2.5″ Focuser, High Res Stepper Motor, V3 Controller, Pegasus Astro Power Box Advance
  • Filters: Optolong L-Pro 2″
  • Exposure Time: 1 hour 50 minutes (22 x 300 seconds) -10°C
  • Exposure Start: 22:10
  • Date: November 09, 2020
  • Location: Voorhees State Park, NJ, United States
  • GPS Coordinates: Lat. 40.68187, Long. -74.89797
  • Temperature: 58°F/14.4°C
  • Bortle Dark-Sky Scale: 4
  • Astrometry.net job: 4031916
  • Avg. Moon age: 23.11 Days
  • Avg. Moon phase: 39.87%
  • RA center: 3h 47′ 10″
  • DEC center: +24° 4′ 12″li>
  • Orientation: 318.678 degrees
  • Field radius: 1.194 degrees
  • Magnitude: 1.6
  • Resolution: 3720 x 2330

Messier 45

This is another picture I wish I had taken more subs. This is a 30-minute unguided shot. These are fifteen, two-minute images stacked together. This is another target that I will have to re-acquire now that I have a better mount and a better understanding of Astrophotography.

Acquisition Data

  • Telescope: Orion ShortTube 80mm f/5
  • Camera: Canon 7D
  • Mount: Orion Atlas EQ-G
  • Software: Photoshop
  • Other Accessories: AstroZap Dew Heater
  • Exposure Time: 30 minutes (15 X 120 seconds)
  • Exposure Start: 00:37
  • Date: October 19, 2015
  • Temperature: 63°F/17°C
  • Bortle Dark-Sky Scale: 7
  • Avg. Moon age: 6.03 Days
  • Avg. Moon phase: 35.80%
  • RA center: 3h 47′ 31″
  • DEC center: +24° 11′ 49″
  • Orientation: 155.887 degrees
  • Field radius:1.792 degrees
  • Magnitude: 1.6
  • Resolution: 4914 x 3185