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 over 7 nights between 1st January & 26th February, 2019.
78x 2 minute exposures with Blue filter (Binned 2x2).
80x 2 minute exposures with Green filter (Binned 2x2).
88x 2 minute exposures with Red filter (Binned 2x2).
534x 3 minute exposures with Luminance filter.
Total Exposure = 34.9 hours.
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)
Linear Fit - To match brightness of RGB channels (RGB Channels Separately)
Channel Combination - To combine RGB channels.
Photometric Colour Calibration - To calibrate colours.
SCNR - To remove green cast.
Deconvolution - To bring out some fine detail & tighten stars, 75 iterations. (Luminance only)
Multiscale Linear Transform - Noise reduction. (Luminace only)
Histogram Transformation - To stretch the RGB & Lum. (Using statistics process to keep background levels evenly)
LRGB Combination - To blend my luminance image with my RGB image.
HDR Multiscale Transform - To recover detail in the galaxy core, with star mask in place.
UnsharpMask - To sharpen with mask in place to exclude stars & background.
Curves Transformation - To darken blacks slightly.
Dark Structure Enhance Script - To pull back some contrast in the galactic arms.
Curves Transformation - To desaturate background, with range mask in place.
Curves Transformation - To saturate nebula, with starless range mask in place.
Export as JPEG and import into Lightroom.
Increase Contrast (+15)
Increase Saturation (+25)
Increase Magenta Saturation (+50)
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?
- 26 February 2019
- How long was the total exposure?
- 34.9 hours
- 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.