M20 Esprit 120 & Canon 60Da

This is the second image from Nova East 2019. Taken on the second of three exceptionally clear nights, I was able to image the object until it hit the trees. This made for an interesting challenge processing as the atmospheric refraction caused the red and blue channels to shift as the object approached the tree line. The solution was to split each sub into its three colour channels and align and combine each red channel, each green channel and each blue channel then rebuild the colour image from the combined colour channels.

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Object M20 (Triffid Nebula) RA 18:02.7 Dec +22:58
Exposure 85 minutes (17 X 5 minutes)
Date August 31, 2019
ISO 800
Camera Canon 60Da DSLR
Optics SkyWatcher Esprit 120  f/7 APO refractor with  a  focal length of 840 mm

 Nova East Star Party, Smiley's Provincial Park, Nova Scotia


Calibration, stacking, stretching in Images Plus . Split star processed with masked stretches.