Posted by R J Andersson at 16:12 on 2013 Aug 27
Hi folks,Having captured NGC7822 a few months ago in Ha, OIII, NII and SII as well as RGB the challenge was to integrate all the data into what, I hope, is an attractive package. Here’s the final result:A 2048×2048 pixel version can be found here.TEC140, ML16803, Astrodon 3nm filters8 x 1500 secs Ha, 18 x 1500 secs OIII, NII & SII8 x 200 secs R, G & BProcessed in PixInsight and Photoshop.The palette choice, ordered by atomic weight with hydrogen = red, oxygen = orange, nitrogen = green with a splash of blue and sulphur = blue, seems to work for this object. White balance was set where hydrogen, nitrogen and sulphur reached their maximal values. I think the palette has virtue, both aesthetically and as an aid to seeing what is going on. It also means that there is a chromostereopsis effect with the whiter and bluer stars and, to some extent, the whiter nebulosity appearing to float slightly in front of the redder parts of the image. Such a 3D effect is pure fiction of course, but fun if you like to let your imagination lose. If you don’t see this effect then you may need to relax your eyes slightly as you view the image. If you still don’t see it then maybe you just have really good eyesight. Best seen on the larger image and, if possible, with a dark surround.I continue to be amazed by what I can see from my back garden here in the Cotswolds with a fairly modest ‘scope, albeit with a raher less modest camera and set of filters!Bob.