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NGC 6914 and gas clouds near Sadr in the middle of Cygnus

Started by The Thing, Aug 07, 2022, 19:23:53

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The Thing

I don't know why the colour went this way but I quite like it. The only thing I did differently was use SNCR after Photometric Colour Calibration before everythng else. I'm still amazed I can get this out of my old Meade SCT which never used to produce nice pics nearly to the edge of frame!

This is 110x120s (3h40m) light frames uncroppped, 20 dark, 10 dark flat, 10 flat, at Gain 1600 (Unity camera gain = 1 photon = 1 electron), Offset 30, Temp-5C.

Image date, time and location:           2022-08-06, Manche, France
Telescope aperture and focal ratio:   Meade LX90 8" UHTC, Baader Alan Gee II Telecompressor at f6
Camera and filters used:           QHY294PROC, Optolong l-enhance tri-band filter
Processing applied:                   Pixinsight, Affinity Photo

Cloudy? ¯\_(ツ)_/¯ (Gallic shrug :))

ApophisAstros

Nice , Duncan did you see my wider field of the same target on 7th July.?
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

Carole

That's a really nice result for this target, the dark nebulae are showing up well as are the blue reflection nebulae.  As you say it has come out a strange colour, I bet it is that SNCR that caused it.  Particularly nice considering it was done with your old slow SCT. 

Carole


The Thing

Quote from: ApophisAstros on Aug 07, 2022, 20:05:06Nice , Duncan did you see my wider field of the same target on 7th July.?
Roger

Hi Roger, Yes I did, that is a very nice image. Strange mine ended up the same sort of colour scheme :o.

My l-Enhance filter emulates Ha and OIII filters with a bit of Hb thrown in for luck so I suppose when I used SCNR "The Subtractive Chromatic Noise Reduction (SCNR) technique has been implemented mainly to deal with green noisy pixels." it completely changed the colour balance that had been set in the previous step by replacing the green pixels by its magic method.
Cloudy? ¯\_(ツ)_/¯ (Gallic shrug :))

ApophisAstros

RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.