Color Balance Adjust after SCNR?

[sreilly]

I am working on a straight RGB image of M51 for now. The rgb image has been combined, cropped, DBE applied, background neutralized, color balanced by using the core of the galaxy and a sample clear background. There is a strong green hue to the image which I use the SCNR tool on. I have the Histogram adjust window open with tracking on and see the rgb peaks well aligned. After SCNR is applied there is a shift and the alignment is not as close as before. Is there a need to adjust the color again? Below are before and after SCNR screen captures with the Histogram process open and tracking.

[jkmorse]

Steve,

The issue is that you have different goals in that image.  You want the background to be balanced as between RGB but you need to get rid of the green in the target and stars.  In situations where only the target needs the adjustment I always apply a luminance mask to the image before applying SCNR.  That way you protect the balanced background.  Without the mask, your background has a reddish/purply hue.

Also, which settings are you using in SCNR.  It makes a difference in how the tool attacks the green.

Best,

Jim