Galaxy in "natural" color. Narrowband channels are mixed to match visible spectrum. Red=80% H-alpha+20% S-II, Green=O-III and Blue=80% O-III+20% H-alpha to compensate otherwise missing H-beta.
Galaxy in HST-palette, Red=S-II, Green=H-a and Blue=O-III
It's a Galaxy season but since my light pollution is so bad, I'm not able to do good broad band imaging, needed for targets like Glaxies.
I made this experiment to see, if it's possible to shoot Glaxy with NB-filters, there is some Broad band luminance used, it's shot with a Hutech light pollution filter.
Kind of interesting to see, how emission areas pop up visually, there was strongish signal in H-a and S-II,
O-III was weaker but there was couple of srong O-III regions, they are seen as Blue in a HST-palette image. There was some very weak O-III signal in a largish area around the Galaxy core, it can barely seen as a Bluish hue in the both images.
Processing work flow:
Image acquisition, MaxiDL v5.07.
Stacked and calibrated in CCDStack.
Deconvolution with a CCDSharp, 30 iterations.
Levels, curves and color combine in PS CS3.
Broadband data is mixed to a narrowband channels in PS.
Telescope, Meade LX200 GPS 12" @ f5
Camera, QHY9 Guiding, SXV-AO @ 10Hz
Image Scale, 0,75 arcseconds/pixel
Exposures,
H-alpha 10x1200s, binned 1x1
S-II 3x1200s binned 2x2
O-III 4x1200s binned 3x3
Luminance,
Hutec LP-filter 6x1200s
Plain narrowband images:
No broad band component, only H-a, S-II and O-III.
Narrowband channels are mixed to match visible spectrum. Red=80% H-alpha+20% S-II, Green=O-III and Blue=80% O-III+20% H-alpha to compensate otherwise missing H-beta.
No broad band component, only H-a, S-II and O-III.
Galaxy in HST-palette, Red=S-II, Green=H-a and Blue=O-III
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