Crescent Nebula – A Collaboration

So, Bostronomy and I did a thing! After the recent APOD winner that featured the Crescent Nebula as a collaboration between three individuals, we decided to take our data on the same target and see if we could combine them. It began more as a test – we did not set out to do this when we first gathered data on the target – and only I had calibration files for my light frames, but I took our data, ran it through Astro Pixel Processor and behold, we were able to combine our data and process it!

Above, we have that data processed without simulating a luminance layer.

61 x 420s –
Meade Series 6000 80mm Triplet APO Refractor
Canon EOS Ra
Ho-Tech Field Flattener
Optolong L-eNhanced Filter

Full calibration frames – dark, flat, dark flat and bias frames. Data taken over 3 nights.

50 x 300s
Explore Scientific ED102
ZWO ASI 2600mc-Pro
Ho-Tech Field Flattener
Optolong L-eNhanced filter

No calibration frames…

I stacked the images in Astro Pixel Processor, letting it know that the images were shot at different focal lengths and with different optics. I used different LNC and Multi-band blending settings to see what ended up the best (in my opinion) – This image was done with a LNC setting of 2nd degree and 6 iterations. From there, I let APP do a stretch, normalize the background and I did a light pollution removal. From there I took it in to Photoshop. In Photoshop, GradientXTerminator was used on its lowest settings with no background calibration. Starnet was not used. Astronomy Tools Actions used to remove noise (Deep Space Noise Removal) and to make stars smaller. No sharpening. Most processing was done in Camera RAW filter to set Vibrance & Saturation. The black, white, shadow and highlight were also used, as well as some minor contrast and exposure changes. Color mixer (in RAW Filter) was used to lightly boost red and blue saturation. For the starless, I did put it in starnet. For the inverted, I simply used Photoshop

The only difference here is that I took the red channel from the starless image in the first group and added that as a slight luminance layer. I set it at 5% opacity and adjusted the curves a little bit to try and bring out a little more nebulosity. The downside with doing it this was is that it can make it appear a little more pinkish then intended.

As mentioned before, this wasn’t planned at all, so we are hoping with doing an actual plan we will be able to produce something a lot better! Stay tuned!

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