Cookie consent

AstroBin saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing AstroBin without changing the browser settings, you grant us permission to store that information on your device.

I agree
Contains:  IC 3476, M 88, NGC 4501, NGC 4477, NGC 4474, NGC 4473, NGC 4461, NGC 4459, NGC 4438, The Eyes, NGC 4435, NGC 4425, NGC 4413, M 86, NGC 4406, NGC 4402, NGC 4388, M 84, NGC 4374
Getting plate-solving status, please wait...
Makarian's Chain and M88, 


            Andrew Klinger
Makarian's Chain and M88

Makarian's Chain and M88

Technical card

Resolution: 3389x2502

Dates:April 10, 2018

ZWO B 1.25": 50x180" (gain: 76.00) -20C bin 1x1
ZWO G 1.25": 40x180" (gain: 76.00) -20C bin 1x1
ZWO L 1.25": 167x180" (gain: 76.00) -20C bin 1x1
ZWO R 1.25": 43x180" (gain: 76.00) -20C bin 1x1

Integration: 15.0 hours

Darks: ~64

Flats: ~30

Bias: ~200

Avg. Moon age: 24.10 days

Avg. Moon phase: 29.81%

Bortle Dark-Sky Scale: 3.00 job: 2070179

RA center: 187.136 degrees

DEC center: 13.499 degrees

Pixel scale: 2.527 arcsec/pixel

Orientation: 191.794 degrees

Field radius: 1.479 degrees

Locations: Atoka dark site, Atoka, Oklahoma, United States

Data source: Unknown


I'm ending this year's galaxy season with the ultimate existential crisis!
Seen here as the fish hook shape is what is known as "Makarian's Chain", a group of galaxies with an average distance of 50 million light years from Earth. These galaxies are all a part of the Virgo Supercluster, which the Local Group (containing our own Milky Way galaxy) is all a part of. But those aren't the only galaxies in this image. Every fuzzball in this picture that doesn't look like a star is a galaxy, each with 100-400 billion stars, and statistically speaking, many of those stars will have a solar system. As a little bonus, I framed the beautiful spiral galaxy M88 in the lower right corner.

OTA: William Optics GT81 w/0.8x reducer (382mm fl at f/4.7)
Mount: Orion Sirius EQ-G (HEQ-5)
Guidescope: Orion 50mm guidescope
Guiding camera: Orion StarShoot Autoguider
Imaging camera: ZWO ASI1600MM-Cool


Location: Atoka, Oklahoma (Bortle 3), and Fort Griffin State Historic Park, Texas (Bortle 3)
Dates: 4/10/2018, 4/14/2018, 4/15/2018, 5/5/2018
Gain: 76 Offset: 15
Camera temp: -20C
L: 167x180"
R: 43x180"
G: 40x180"
B: 50x180"
Total integration time: 15hrs
64x darks per calibration
30x flats per calibration
200x bias (master bias in library)

Batch PreProcessing script to generate calibrated images
StarAlignment to register all frames to a reference L
LocalNormalization on RGB frames
DynamicCrop each master
DBE on each master
LinearFit G and R to B

RGB processing:
SCNR green 50%
ArcsinhStretch for a small stretch
HistogramTransformation x2 to finish the stretch
SCNR green 100%
ExponentialTransformation w/ mask to push the galaxies slightly brighter
CurvesTransformation for saturation
ColorSaturation to target blue saturation

L processing:
HistogramTransformation x2 to stretch image
Duplicated the image to create a starless version, using a starmask and several iterations of MMT and MT. Then pushed the faint nebulosity in the starless version using PixelMath expression: "1-(1-$T)*(1-$T)"
Combined the starless version with the image using PixelMath expression "F=0.4; (1-(1-$T)*(1-s)*F)+($T*~F)" followed by the same expression with F=0.2 (s=starless photo).
HistogramTransformation to move blacks in
LocalHistogramEqualization to improve contrast within galaxies
MultiscaleLinearTransform for slight sharpening

Combined L and RGB with LRGBCombination tool
CurvesTransformation to neutralize background color
ACDNR for slight noise reduction
HistogramTransformation to move black point in
Resampled to 40% for web posting



Andrew Klinger
License: None (All rights reserved)

Sky plot

Sky plot


Makarian's Chain and M88, 


            Andrew Klinger