Probable colormanagement bug in PL6

[Egregius ([Greg] (Micro 4/3 + Win11))]

@Photo-DKO

Yes, thank you. This diagram shows exactly where I believe the bug is. When using the Classic gamut, this diagram looks correct. When switching to the Wide Gamut, it seems like the first step after the raw conversion (“assign camera profile”) is not executed until we actually enable the Color Rendering module. So what we initially see is incorrect saturation. This is inconsistent, which is the problem.

Just for the sake of clarity: that diagram doesn’t come from DxO and hasn’t been verified by DxO. It’s a collaborative effort to understand and roughly estimate how color rendering in PL6 works.

The crux of your concern has been extensively discussed in the forum. That is:

@Photo-DKO

When we select the Classic (approx. Adobe98) Working Color Space colormanagement seems to be working as it’s supposed to (as far as dispaying on screen goes, not talking about exporting to DNG here, there’s also an CM issue with that). But when we select the new Wide Gamut option, CM only kicks in if we enable the Color Rendering module. This shouldn’t be.

By all means, submit a bug report. But as far as I can tell, what you’re seeing is by design. When Color Rendering is off, you get different default color renderings (not a null rendering) depending on the working color space:

Classic WCS: Color rendering off = DxO Camera Default color rendering
DxO Wide Gamut WCS: Color rendering off = Neutral color rendering

The first is legacy behavior we see in PL5 and earlier. The second is a new behavior introduced with the DxO Wide Gamut WCS in PL6. It’s controversial, but DxO has stood by their decision so far.

Colour spaces - different renderings

I think several things got mixed up. If there are no out of gamut colors in the srgb space, there should be no difference in rendering between any working color spaces greater than srgb. The difference you see is I believe due to different default renderings applied for the classic rendering and wide gamut rendering. The classic one will use the generic camera style. The wide gamut one will use the neutral style as default. Can you apply the Adobe flat profile to the classic rendering? It shou…

Picture is altered even if I disable all preset corrections

Dear All, Thanks for all your input. @Egregius you pointed me into the right direction, its was the color space. I created this profile in an earlier version of PL and, I guess, this made it using the classic mode. As soon as I switch to DxO Wide Gammut, the both images (“no corrections” and “preview of the corrections”) looked the same if I switch off all corrections. I’m wondering why: a) the uncorrected version uses DxO Wide Gammut. Is this default in PL6? b) Why there are such big differ…

To further address your original post:

@Photo-DKO

We shouldn’t be able to actually see any differences in saturation on-screen between both WCS’s, the benefit of a larger WCS being mostly smoother, more accurate gradients, whether we apply luminance curves or film sim’s (Color Rendering) or not.

This isn’t true. A larger WCS does allow more saturated colors to exist in the intermediate stages of the pipeline. It does not ensure smoother, more accurate gradients. You might get that from a larger bit depth:

Search results for ‘10-bit #dxo-photolab:feature-requests’ - DxO Forums

I hope that helps.
Greg