HSL Selective Color

@astrohound24 Greg, your particular question about stars only is a hard one since APP currently doesn't allow for that. Also, HSL Selective Colors isn't so much for color saturation but more for changing the color space. In some cases this difference may be subtle but it is important.

If you want to make more orange visible (meaning convert similar colors to appear orange) then in HSL Selective Color you can select the ALL color channel.

Next you select a range. for adding more orange a possible choice could be "background - 75% of range" or one of the "background + X*noise - 75% of range" selections.

You can then adjust the selected range by using the LOW and HIGH sliders.

You can click the "show color selection" button to show which pixels will be selected. For instance, on my image of NGC 7000

selecting "background + 3*noise - 75% of range" shows this selection:

Once you're happy with the selection, you can move the R<->CY and G<->MA sliders both to the left by, say, 30% and click "calculate current adjustments". In my case I get this:

Note that when you use the LOW and HIGH sliders, you'll need to click the "show color selection" again to show the newly selected pixels. APP doesn't automatically update the view.

I hope this answers your question.

Wouter

Yes this helps. Thanks! When selecting backgrounds I guess one can experiment by checking which selections show which pixels will be affected by looking at the show colors selected tab. I was just trying to make my orange stars more saturated and blues, etc. Thanks again. 

Greg

One more question. If HSL color is more for colorspace than about saturation, what is good way to increase saturation of something like the brighter stars in an image or anything in the image for that matter? Thanks!

GM

@astrohound24 The saturation slider in the tools section on the right hand side of the APP window would need to be used for that. APP doesn't have masking capabilities to only adjust the saturation of the stars, however.