I take this picture with Canon EOS 200d II, 18-55mm IS STM with jpg+RAW setting. When I open RAW in RT (RawTherapee 5.8, released on 2020-02-04) , with default profile auto-match low iso. There is strange color, red and blue line at the bottom see my attach picture. But the jpg that came from camera there is none. Even neutral also reveal some of this strange color line too.
What cause this? Why? What is miss? And how to solve this?
Avoid color shift is in Lab* adjustments? As I have no avoid color shift in Chromatic Aberration Correction. I’ve attach picture to you. Anyway with or without tick that option I see no difference in picture.
My work around so far is to crop it away.
I’ve attach RAW file link above maybe you can try.
Yes! It fix now! How come? So what is this option for? When to untick it? Should I always untick it?
This is compare before and after I untick “avoid color shift”
When using raw ca-correction, the image gets a small colour shift. For most of the images, you can fight this color shift by enabling Avoid colour shift. But (as always) there are some border cases (for example your raw has very strong CA at the bottom) where this does not work good. In your case it introduced a colour bleeding from the region with very strong CA to the region above.
Here’s a screenshot to show the very strong CA at the bottom of your file which caused Avoid Colour shift in `Raw CA correction´to fail for this region:
