Presenting (We all know it, right?) Messier 31, the Andromeda Galaxy. This image is the product of a fun basic-equipment side-project I’ve wanted to work on for a while. Captured with an Olympus OM-D E-M1 Mk.II, Olympus 40-150mm Pro zoom lens, and iOptron SkyGuider Pro, producing a relatively modest 2.5 hours of color data and 2 hours of Hydrogen-alpha (red channel from integration captured using Hydrogen-alpha filter).

The project goal? Create a nice image using basic equipment to show that a nice image doesn’t require sinking many thousands of dollars into equipment (rather, that acquisition process along with post-processing knowledge and technique are important, affordable, pieces of the puzzle). An homage of sorts to a quip Ed Ting shared in a video, which also reminds me of general photography: “You spend a lot of money to find out you didn’t need to spend a lot of money.” (Paraphrased to the best of my memory.) My hope is that I can point to it in conversations where people are assuming those many thousands of dollars of equipment are requirements. Or rushing to conclude that upgrading equipment is the only sound solution to resolving frustration encountered in a challenging hobby.

M31 seemed like the perfect target for this, being familiar to everyone, a great widefield target for lenses, and short-session friendly.

Under “post-processing details” below I included a text file link outlining, in detail, the editing process.

I won’t be abandoning my nicer mounts, telescopes, and astronomy cameras, of course. For a rather long list of reasons. And are certainly challenges and limitations to overcome with basic equipment. I just want to be able to show that those things aren’t necessary to really enjoy the hobby.

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Lights RGB 100x90s ƒ/2.8 ISO1000
Calibrated with Darks, Flats, Flat Darks
Antelope Island State Park, Utah, USA (Bortle 4)

Olympus OM-D E-M1 Mk.II (M43)
Olympus 40-150mm ƒ/2.8 Pro Lens (150mm)
iOptron Sky-Guider Pro
ZWO ASIAir Pro with ZWO 30mm Guide Scope (ASI120MM) and additional “dummy” camera for non-synchronized dithering (ASI120MM).

Lights Hydrogen-alpha 24x300s ISO3200
William Optics RedCat 51 (with above)
Which enables use of: Astronomik Hα 12nm
I would have used the same zoom lens, but I have no way to mount my 2" filters. Still, I thought it would be worth including a demonstration that a stock sensor can still be used to accent Hydrogen-alpha nebulosity in galaxies.

Capture Details
Camera was controlled with an intervalometer. Mount was controlled with an ASIAir Pro. Dummy exposures were captured using a second guide camera to trigger timed dithering (destroys current exposure). Slightly reframed on a couple occasions (nudged mount) to dither on both axes and mitigate walking noise. Flats captured with diffused panel and darks captured after with intervalometer. I opted for 150mm instead of 300mm (another lens) because 300mm would be tight and 150mm gives me room to crop outer permitter of image circle.

Post-processing details (extensive notes)
https://tinyurl.com/JPAndromeda
Read below for a summary, or click the link above for deeper details and notes. Because this is a “you can make a decent image with basic equipment” photo, I wanted to include more specific post-processing details for anyone who may be curious.

Post-processing details (summary): PixInsight and Adobe Photoshop. Integration with normalization (NSG) and drizzle. Background removal with ABE and DBE. Color calibration with some dedicated adjustments and SPCC. Hα data blended (continuum subtraction) using red channel from data captured with 12nm Hα filter (sensor non-modified). Deconvolution and galaxy and stars images processed separately. Galaxy stretched and saturation/colors adjusted with GHS and curves transformation (with some masked adjustments). Noise reduction handled primarily with NoiseXTerminator (always never more than needed). Tools including Local Histogram Equalization, HDRMT, Dark Structures Enhance, Generalized Hyperbolic Stretch, Curves Transformation, and PixelMath used for additional refinement. Stars processed with deconvolution (masked to accent small stars for star reduction), EZ Soft Stretch and Generalized Hyperbolic Stretch, star reduction (Bill Blanshan’s PixelMath). Stars and galaxy image processed in Adobe Photoshop. In Photoshop, additional curves and color adjustments, cleanup, refinement, and blending.