M31 - The Andromeda Galaxy
Sat Oct 12 2024
I think we've broken a record here in Kentucky - we've had something like 9-10 clear nights in a row! This is the most exposure time I've ever collected for one image and it's clear how having more data makes the processing go so much better. Previously, I have never been happy with the methods I've tried to combine Ha with RGB for a galaxy. Over the last week or so, I've been preparing for how I was going to handle the post-processing on this image and tried many different methods including using Continuum Subtraction, NBColorMapper, the CombineHaWithRGB script, etc. but ultimately settled on a much more simple method. I created my RGB master, ran SPCC on it and then used ChannelCombination to add my Ha data in the red channel and left the green and blue unchecked and ran that process on the RGB master. Then, after running SPCC again on the combined image and adjusting saturation, I was able to get this to look like what I had envisioned.
About this object
- Type
- Galaxy
- Constellation
- Andromeda (the Chained Maiden)
- Distance
- ~2.5 million light-years
- Apparent magnitude
- 3.4
- Apparent size
- 177.8′ × 69.7′
- Also known as
- Andromeda Galaxy
- Catalogue designations
- M 31, NGC 224
The Andromeda Galaxy (M31) is the nearest large spiral galaxy to our own and the most distant object visible to the naked eye. Containing roughly a trillion stars, it is on a collision course with the Milky Way and will merge with it in about four billion years.
Acquisition
- Antlia 3nm Narrowband H-alpha 36 mm: 174 × 3m (8h 42m)
- Antlia V-Pro Red 36 mm: 539 × 1m (8h 59m)
- Antlia V-Pro Green 36 mm: 505 × 1m (8h 25m)
- Antlia V-Pro Blue 36 mm: 525 × 1m (8h 45m)
- Total integration: 34h 51m
Equipment
- Telescope / Lens: Astro-Tech AT72EDII
- Camera: ZWO ASI2600MM Pro
- Mount: Celestron CGEM II
- Filters: Antlia 3nm Narrowband H-alpha 36 mm, Antlia V-Pro Blue 36 mm, Antlia V-Pro Green 36 mm, Antlia V-Pro Red 36 mm
- Guiding scope: ZWO 30mm Mini Guider Scope
- Guiding camera: ZWO ASI224MC
- Accessories: Astro-Tech .8X Reducer for F6 (ATR8), ZWO EFW 7 x 36mm
- Software: Pleiades Astrophoto PixInsight
Astrophotography by David Joyce, AstroDavido.