Sadr HRGB redone

[Earl]

Much happier with the way this looks now, but still feels overly pastel, but that i think is due to using Ha for luminance.

Full size:

https://dl.dropboxusercontent.com/u/43788925/Sadr%20Redone.jpg

Id welcome plenty of feedback espeically on the colour.

Thanks to Julianr for solving my binned star isssue with a bit of convolution.

[ollypenrice]

HI Earl,

Why don't I use Ha as luminance? Because Ha isn't luminance, it's deep red. If you apply it as L you re-illuminate your green and blue as if they were deep red but they are not, and cannot be, that. Luminance, in honest imaging, is red and green and blue. Anything ignoring this fact is a distortion. So, yes, I'm an aesthetic imager but I feel I have to respect certain rules and I also think these rules make for better images.

I see your deep background sky as blue dominated and then there's a mi-brightness bulge in green before red takes over at the top. I think that if you start with a well balanced RGB you can add Ha to red in blend mode lighten and keep pulling the colour back to match the original RGB with each addition of  Ha. This is what I would recommend. You are, of course, perfectly free to tell me to clear off!!!

Health warning: I have been awake/working for around 18 hours a day for quitesome days so my judgement is not at its best...

Olly

[Earl]

Cheers Olly, perfecly valid points, I should grab a set of Lums and try it out LRGB and L+Ha RGB

[MartinB]

Plenty of dust there Earl, you have some great data.  The stars seem a little over saturated and over sharpened and, as Olly says, the background sky is a tad blue, and as you say the Ha is moving towards the dreaded salmon effect  

I agree with Olly about the problems of using Ha for the luminence channel, however, if all the detail is coming from Ha then it can be a great loss if you don't use it to it's full potential.  It all becomes a compromise and there are many different ways of trying to address the problem.  A lot depends on the target and the data you have, there isn't a fixed processing routine that works but try this -  Blend in the Ha to your red layer, as Olly suggests and create an RGB image.  Process as usual but leave a substantial pedestal for the black point.  Create a duplicate RGB layer and set blend mode to "soft light" then put your luminence on top using luminosity as the blend mode.  You will probably need to drop the opacity to around 70%.  The addition of the soft light blended RGB layer seems to really help the colour come through.  There's lots of dirty work arounds you can use which would outrage the creators of PixInsight!

[Earl]

I aim to grab the lum data tonight this will open up options