M27, Dumbbell Nebula

[turfpit]

Captured over 4 nights, late May 2020, 4h 9m integration.

M27-LRGB.JPG (213.9 KiB) Viewed 1385 times

Dave

[oopfan]

Thanks for the plug, Dave. I'm still working on the documentation.

I developed that tool to help explain why my 11.6-hour M81 was skewed toward the red. The problem is that the atmosphere attenuates blue and green wavelengths more severely than red at any given altitude above the horizon. If it were possible to capture the red and green and blue frames simultaneously, such as with an OSC camera, then this would not be an issue, but since mono camera users capture a series of red frames first then green and then blue the altitude is different for each filter. All said and done before you go to post-processing you need to analyze all the frames to get the SNR balanced across the stacks. That is what my Analyzer tool does. For my M81 the red stack had a slightly higher SNR so I removed a few red frames. For Dave's M27 he had too many red frames as well as green frames.

[umasscrew39]

Beautiful image- great color and sharp stars- congrats!!!

[turfpit]

Thanks Bruce.

Dave