Galaxies

Bode's Galaxy

Bode's Galaxy (Messier 81), a spiral 12 million light-years away in Ursa Major, photographed by Pete Lawrence.

Target details

Bode's Galaxy, Messier 81, is a large spiral galaxy about 12 million light-years away in Ursa Major. Because it's relatively close, big, and has an active core hiding a supermassive black hole, professional astronomers have studied it in great detail. Its size and brightness also make it a favourite target for amateur astronomers.

Capture details

Data captured 27th & 28th December, 2017.
19x 3 minute exposures with Blue filter.
29x 2 minute exposures with Green filter.
17x 3 minute exposures with Red filter.
117x 1 minute exposures with Luminance filter.

This was the first image captured with my Atik 428EX CCD camera. The target certainly required much more data but the weather & the full moon would not allow me any more data for at least another 2 weeks so I decided to process the data I had.

Equipment details

Skywatcher Quattro 200 CF
NEQ6 Pro
Atik 428EX Mono
Skywatcher ST-80
QHY5L-II

Processing details

This image was processed in Pixinsight & Lightroom.
Calibration and Stacking in Pixinsight using Batch PreProcessing
Dynamic Crop - To remove black edges & integration artifacts. (Each Channel)
Dynamic Background Extraction - To remove gradients. (Each Channel)
Deconvolution - To bring out some fine detail & tighten stars, 50 iterations. (Each Channel)
Multiscale Linear Transform - Noise reduction. (Each Channel)
Histogram Transformation - To stretch the image
ChannelCombination - To combine RGB channels.
Photometric Colour Calibration - To calibrate colours.
SCNR - To remove green cast.
LRGB Combination - To blend my luminance image with my RGB image.
TVGDenoise - Some additional noise reduction, rangemask in place.
HDR Multiscale Transform - To recover some detail in the galaxie's core.
UnsharpMask - To sharpen with mask in place to exclude stars & background.
Curves Transformation - To boost contrast.
Dark Structure Enhance - To boost detail in dark areas.
Curves Transformation - To boost saturation.
Histogram Transformation - Clip Blacks.
Histogram Transformation - Clip Blacks with mask in place to protect galaxy.
Curves Transformation - Increase Saturation with previous mask inverted to protect background & stars.

Export as JPEG and import into Lightroom.
Contrast Boost (+15)
Clip Blacks (-25)
Increase Vibrance (+15)

Export final JPEG for upload.

Quick facts

What is Bode's Galaxy?
Bode's Galaxy, Messier 81, is a large spiral galaxy about 12 million light-years away in Ursa Major. Because it's relatively close, big, and has an active core hiding a supermassive black hole, professional astronomers have studied it in great detail.
Where is it in the sky?
In the constellation Ursa Major.
What are its catalogue names?
M81
When was this photo taken?
28 December 2017
What equipment was used?
Skywatcher Quattro 200 CF, NEQ6 Pro, Atik 428EX Mono, Skywatcher ST-80, QHY5L-II
Where was it taken from?
Lisburn, Northern Ireland.
Can I use this image?
It is © Pete Lawrence, all rights reserved. Personal use such as a wallpaper is fine; for anything else please ask first (see image use).
Bode's Galaxy: astrophotograph by Pete Lawrence