Bizarre bug(?) in Lightroom cloning functionality

StewartR

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Stewart
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I've discovered a weird phenomenon in Lightroom. I'd be grateful if anybody could explain whether this is a bug, a feature which I hadn't understood, or simply user error.


The situation is that my photo contains out-of-focus highlights caused by the sun filtering through trees in the background. Unfortunately some of them are totally burnt out, but I can rescue it by cloning some not-burnt-out highlights into the burnt-out area. Since the highlights are round, it seemed ideally suited to the cloning functionality within Lightroom rather than exporting it into Photoshop.

The first screenshot shows two cloning operations in process. Both clones are sampled from the same area of the photo. To the right, cloning into an ordinary (not burnt-out) area of the photo is successful. To the left, cloning into the burnt-out area results in a magenta fringe to the cloned area.

LR-Clone-1.jpg


The second screenshot has the highlight warning turned on, so you can see the burnt-out area in red. Again there are two cloning operations in process, and again they are both sampled from the same area of the photo. To the left, cloning into an area which is completely burnt-out results in a complete magenta fringe. To the right, cloning into an area which is only partially burnt-out results in a partial magenta fringe. The fringe here corresponds roughly to the burnt-out area.

LR-Clone-2.jpg


Any ideas? Bug, or user error? Should I just cut my losses and do it in Photoshop?

Cheers
Stewart
 
was it clone or heal, as heal samples from the surrounding area aswell as the target area. tbh local adjustment in LR sucks
 
was it clone or heal, as heal samples from the surrounding area aswell as the target area. tbh local adjustment in LR sucks
Clone, definitely.

Anyway, if it were in healing mode that still wouldn't explain the magenta fringing, or why I only get it when I'm cloning into burnt-out areas.
 
I get this too whenever trying to clone anything that's 'hot'. Hasn't come up that often though so never paid it much thought - just assumed I was having a rubbish moment.
 
Yes I experienced something similar when cloning a burnt out reflection in Lightroom 1.x a week or two back.
 
UPDATE: Just downloaded Lightroom 3 Beta. Still no difference.

Is it REALLY a bug? If so many people have experienced it, in such repeatable circumstances, you'd think Adobe would have fixed it by now. Is it an artefact caused by some settings within the program?
 
UPDATE: Just downloaded Lightroom 3 Beta. Still no difference.

Is it REALLY a bug? If so many people have experienced it, in such repeatable circumstances, you'd think Adobe would have fixed it by now. Is it an artefact caused by some settings within the program?
It might be worth reporting the bug in the beta, maybe they'll fix it for the official version.
 
That looks to me like an effect of single channel highlight clipping and recovery. The highlight warning will show anywhere any one RGB channel has maxed out, and the recovery option will try to use the others to fill in (effectively guess) what details was there. If two channels are clipped then it more difficult (insert some calculation code that i can't remember...).

Anyway... i'm guessing that in trying to blend a clipped with a non-clipped area there is a similar algorithm used, and that can introduce a colour cast which you are seeing as the magenta - it's basically an area of very high recovery causing coloring. You can see the effect if you take a shot with a strong cast to it that has blown highlights - say one shot under stage lighting with coloured lights. When you use recovery you'll see the coulr cast change. If you have the RGB histogram showing on develope you can sometimes see recovery operating on one channel more than the others.

The only suggestion i can make to solve it, short of reporting it as a bug, is to see if changing the recover setting for the image helps at all.
 
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