Lightroom 5.7: color artifacts with A7s and A6000 files using Camera calibration profiles

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I'm seeing some really obvious chroma artifacts / false colors with RAW files from either a Sony A7s or A6000 when using any of the Adobe-provided Camera calibration profiles that emulate Sony's rendering.

This seems to happen at any ISO, and is very frequent.

If I use the Adobe Standard calibration profile then things look normal, but that's might just be because it produces rather desaturated images compared to the "sony" profiles.

Prior to those Sony cameras I was using Nikon DSLRs for which I had somewhat similar issues when using the first version of the Nikon camera profiles.

Those issues got fixed when Adobe released the "v4" camera profiles.

Here are examples:

Adobe Standard profile:


Camera Landscape profile:


Adobe Standard:



Camera Standard:

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drseb

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Posted 3 years ago

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Steve Sprengel, Champion

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If you want Adobe (and the rest of us) to look into this, please provide your raw file(s).

Upload to www.dropbox.com and post a Public Share link in a reply, here.
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drseb

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Thanks Steve. Here is a link to couple pictures:
https://www.dropbox.com/sh/317ipp8gb8...

Also, here is the mix of green/purple blocks and tint I'm seeing for one of the guitar pictures:
Camera Landscape:


versus Adobe Standard:
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Steve Sprengel, Champion

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Looking at those three sample images, it isn't obvious this isn't just color noise-reduction that isn't quite smooth enough or that light is different colors at different angles. I can reduce the color discontinuities by turning up the Color NR - Color Smoothness slider all the way and if I turn off the Color NR entirely, the gray fur is actually a mixture of green and purple spots due to the high-ISO. What I'm less sure about is why the darker nose area is purple while the rest is more gray.

Do you have any at ISO 100 shots of skin on a curved surface like an arm or hand or maybe a piece of paper wrapped around something, with different brightness of light on one side compared the to the other? I want to see something where there is no color-noise blotchiness if I turn off Color NR.

In other words the false colors are in the image pixels as color noise at high-ISO.
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drseb

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Thanks for the help!

I added DSC03655 at ISO 250. With Adobe Standard everything looks normal, there is also very little chroma noise with chroma NR disabled. Switching to either Camera standard or landscape the very fine chroma noise becomes immediately obvious and there is a dramatic mix of strange colors on the fur and hands.

Setting the color smoothness to the max does help, though it does cause other issues (at the boundaries between different colors). I'm not entirely convinced the chroma noise is the root cause either because if just use Adobe Standard and try to boost vibrance/saturation/contrast/tone curves to make the picture look similar to the Camera Standard profile, I can never get to see any of these weird colors.

The few ISO 100 I have are landscapes in fairly bright light, none of which really show any issue. I do have a few of kids/friends that I can't share, on these I don't see anything abnormal on skin tones but I do see similar false colors in darker areas (but only when using the calibration profiles other than Adobe Standard).
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Steve Sprengel, Champion

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I'm not seeing a lot of problems with the latest image. There are few noise issues in the darker areas of the fur but the main thing is that the arms are ok.

I think the colors you're seeing are from noise that isn’t being completely eradicated and accentuated by the color and contrast strengthening of some of the simulated camera profiles.

Looking online I see another ISO 1250 camera-jpg that has spots in it, where obviously it is using one of the camera's own profiles, now this is not the larger-scale blotches you're seeing but it does show the noise can be bad at this medium ISO that your other rabbit picture was taken at: http://stuckincustoms.smugmug.com/Mis...


For review, this is what was happening with the D810 problem profiles, which are not what you're seeing, since the D810 boundaries didn't change with more and less Color NR: https://www.flickr.com/photos/3016408...

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drseb

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That first one appears, based on the EXIF, to have been saved with Adobe Photoshop CC. It's unclear to me if this is coming from a RAW picture or the OOC JPEG, but it is fair to assume given the look that it has been heavily processed. I agree the fine chroma noise is obvious, and I'd say I also see somewhat similar blotches (red in this case) in smoke/sky.

The D810 issue is interesting, it seems quite similar to what I saw on D700 RAW files when using the simulated profiles back in 2011. Here is one, with strange green and purple patches on the tree when the Camera Standard profile was used:


Reducing chroma NR doesn't show any obvious chroma noise, but the patches are there.
Now take the v4 profile released in 2012 and everything looks completely normal:


Updated color profiles is all it took to fix this.

There is precedent for those color artifacts being related to color profiles that eventually get fixed. What I'm seeing on the A7s and A6000 still makes me suspect another profile-related issues since using the Adobe Standard profile doesn't cause any such problem (no matter how much I adjust the image to make it look like the Camera Standard profile).

Here's another one from a A6000 at ISO 100, +0 exposure, using the Camera Standard:
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drseb

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Using Sony's own RAW converter, not exactly known for it's top notch quality, I can see some of the purple/green chunks on that first rabbit picture as well. It's just not as segmented as the LR results with camera profiles.
I see them as well on that car picture using Sony's converter. Capture One Express however doesn't show any of that.

Maybe the conclusion is to either change cameras or stick to the Adobe Standard profile...