Galaxies
The Triangulum Galaxy
The Triangulum Galaxy (M33) photographed by Pete Lawrence: a spiral 3 million light-years away and one of the most distant naked-eye objects.
Target details
The Triangulum Galaxy (Messier 33) is a spiral galaxy about 3 million light-years away in the constellation Triangulum. It's the third-largest member of the Local Group, after the Andromeda Galaxy and the Milky Way, yet it's also the smallest spiral in the group, and is thought to be a companion of Andromeda given how they move and how close they appear. It's one of the most distant things you can see with the naked eye. Its core is an H II region, a cloud of glowing hydrogen.
Capture details
Data captured 22 September, 2017.
24x 10 minute exposures at ISO400.
Equipment details
Skywatcher Quattro 200 CF
NEQ6 Pro
Canon 40d (IR Filter removed)
Skywatcher ST-80
QHY5L-II
Processing details
This image was processed in Pixinsight & Lightroom.
Calibration and Stacking in Pixinsight.
Dynamic Crop - To remove black edges & integration artifacts.
Channel Extraction - Split RGB Channels.
Dynamic Background Extraction to each channel to remove gradients. I was more agressive with Green.
Channel Combination - Recombine Channels.
Canon Banding Reduction script - To remove horizontal lines.
Photometric Colour Calibration - To colour calibrate the image.
SCNR - To neutralise green.
Deconvolution - To bring out some fine detail.
Multiscale Linear Transform - Noise reduction.
Histrogram Transformation - To stretch the image and bring out the data.
Curves Transformation - To increase contrast.
Local Histogram Equialisation - To sharpen and increase detail.
Multiscale Linear Transform - To sharpen and increase detail.
Unsharpmask - To sharpen and increase detail.
Local Histogram Equialisation - Increase detail.
Dark Structure Enhance - To increase contrast in inner arms.
Curves Transformation - To improve contrast on entire image.
Curves Transformation - To increase saturation, using rangemask to select galaxy.
Export as JPEG and import into Lightroom.
Increase Contrast (+25)
Clip Blacks (-25)
Export final JPEG for upload.
Quick facts
- What is The Triangulum Galaxy?
- The Triangulum Galaxy (Messier 33) is a spiral galaxy about 3 million light-years away in the constellation Triangulum. It's the third-largest member of the Local Group, after the Andromeda Galaxy and the Milky Way, yet it's also the smallest spiral in the group, and is thought to be a companion of Andromeda given how they move and how close they appear.
- Where is it in the sky?
- In the constellation Triangulum.
- What are its catalogue names?
- M33
- When was this photo taken?
- 22 September 2017
- What equipment was used?
- Skywatcher Quattro 200 CF, NEQ6 Pro, Canon 40d (IR Filter removed), Skywatcher ST-80, QHY5L-II
- Where was it taken from?
- Lisburn, Northern Ireland.