Cover a large area with automask or is there another way?

If I want to use auto mask to mask a subject and all of the areas around the subject (the background) how to do it without the auto mask missing areas? I’ve attached an exaggerated example.

I masked the outline of the bird and then tried to use the same mask to cover the whole area around it so I can basically change the exposure of the background. It seems like every time I try to mask the “background” it misses areas. Is there a better way? Thanks.

Hi Soundchasr,
when the subject is in front of such a ‘clean’ almost unified background always start your efforts on the background. With some luck (some work / exercise) you can reuse a inverted copy of the background mask.

While Automask can work quickly, it is not so easy to get precise selections (to edit the selection).

For the shown example you could try with Control Lines, which like Control Points allow to adjust chrominance and luminance. To exclude (you cannot edit CLs with a mask brush) you then use ‘negative’ Control Lines. – I remember some time ago @Joanna showed a nice example. When she is reading here maybe she can point you to that thread.

I do hope, that DxO will improve these masking possibilities in the future.



You don’t have to mask both the bird and the blue sky. Just mask one of them(I’d say the bird) and then invert the mask to work on the background or better yet, duplicate it and invert one these two. Then you will have two masks, one for the bird and one for the background. Also @Wolfgang is absolutely correct, this would be easier to mask using Control Lines.


@Soundchasr – had seen another pic from you … where @rrblint showed you how to refine ‘edges’.

Downloaded your screenshot and …

did some experiments. → (4,2 MB)

Note – in both VCs I used the same values.

Comparing the VCs at 100%, in VC2 the edges show less ‘halo’ (they were not duplicated).
The refined Auto mask is less effective along the edges, so that the corrections made to the subject blend in better.

Maybe you like to try this on your real pic.


@Wolfgang Thank you for that explanation. That really helps with what I have to do pretty often. I would still like to know if anyone else had the issue where auto-mask doesn’t cover everything. Am I wrong to compare it to LR’s brush mask?