Highlight ghosting / halos when increasing exposure

One of the ugliest effects in photo processing I find halo’s / ghosting around dark objects.
I discovered, that when increasing the exposure, exactly this effect appears.
It looks like it’s still applying some mild version of ClearView Plus (which is disabled).
All values but exposure are set to zero.
It happens with all color rendering profiles (including disabled), some more than others.

I find this behavior rather odd, especially since an image with a matching exposure does not show these artifacts.

Attached is an image with +2.5 exposure compensation.
And the same image with low gamma to show it better.

Is there a way to disable any form of ghosting / haloing? Or could it please be disabled in a future release?

Could you tell us something about the files: are they jpegs or raw; 8 or 16 bit?

What zoom level were you viewing this at in PhotoLab? Is the effect still present when you zoom at 75% or greater? I have occasionally noticed something similar myself but it is not the norm.

Mark

Did you used smartlighting?
And when you push tonecurve do you get the same outcome?
(i remember a post where this behaviour was called in certain circumstances, can’t remember which.)
Try different way’s like contrast and tone sliders, tone curve, smartlighting and exposure to see which has the most halo’s ghosting when you push the brightnes.

@ mark
It is not zoomed in at all, it’s the full width.

@Peter: No, smart lighting is also disabled.

The effect is more prominent with certain color renderings (Color positive film for example)

Canon C-RAW files from a 90D camera.
I’ve tried it with some Panasonic GH5 raws and I can replicate the effect (when really pushing it) as well.

Could be something related to the C-RAW format?
C-RAW files use a lossy-compression algorithm, meaning that some of the image information is lost to save space…Do you have the same problem with your 90D and full-size RAW?

Is it visible in the default version when you look closely?
It’s rather big, the highlighted border, pure guessing:
CA correction issue? If you turn that off does it change?
It’s treebranches against bright sky
What does the rawfile do in a other raw capable program when you push it?
Would it be fine to upload the file so we can see for our selfs?
(lot of questions but we shoot flying ducks in the dark now… :yum:)

@Peter:
My answer was given to Steven but my posts need approval that’s why it appears below your reply.

I am 99% certain that it is an image processing algorithm since the effect only becomes present when boosting the exposure.

1 Like

I haven’t tried that yet but I can recreate the effect with raw files from a Panasonic GH5 and other Canon camera’s.

And attached is a (heavily overprocessed) raw from a 550D camera, where I used the ‘no correction’ preset and only changed the gamma, exposure and set color rendering to Fuji Astia. But it also happens with camera body renderings. The effect is least visible with color rendering disabled, but still there.

Hello @Skies,

Could you, please, provide us with some images+sidecars for the analysis? Please, upload them to upload.dxo.com under your forum name and let us know when ready.

Thank you,
Regards,
Svetlana G.

This appears to be an issue with the way in which DXO recovers highlights. There is a thread over on the Retouching forum started by Digital Nigel which shows the issue in detail.

My “guess” is that it is some how linked to the way DXO processes images. I wonder if DXO breaks down the image into blocks and processes each block separately? Is this how DXO is able to apply different processing to different parts of the image to achieve effects like smart lighting?

If you look at the image posted by Nigel you can see that where the sky is “separated” from the rest of the sky by branches it receives different processing. It also appears to be related to where one or more of the channels is blown.

The high contrast sky - tree boundary appears to yield a similar effect.

This issue has a significant impact on highlight recovery of blown sky areas and is reproducible.

I’ve just uploaded two raws with *.dop files (the two from the samples I posted)

Hello,

Thank you, got them. We’ll investigate.

Regards,
Svetlana G.

Was a solution to this issue ever found?

Hello,

Not yet found. You’ll be notified when the Lighting will be improved for this case.

Regards,
Svetlana G.