Icc utilisation

En quoi consistent le profil basé sur une RAW linéaire de référence et un profil basé sur une référence DxO realistic, et où les trouver?

Hi Denis, please elaborate on your question. It’s fairly generic as it is now and some context or info about what you are looking for can help give a better answer.

Dans le département Couleur, plus précisément dans Rendu des Couleurs, il est possible d’installer un profil ICC, et il est proposé 2 choix:

  1. Profil basé sur une image RAW linéaire de référence.
  2. il s’agit d’un profil basé sur une référence DxO realistic.
    Ma question est: en quoi consiste une image RAW linéaire et qu’est exactement une référence DxO realistic, comment les appliquer?
    Avec mes remerciements,

In order to create a colour profile, you need some software and a print containing patches of known colours. The software will then calculate a profile that corrects the differences that exist between the rgb values in the rendition of the patches in the shot and the rgb values of the reference patches.

Adobe provides many profiles with its free DNG Converter. They are not based on your own camera though. If you want profiles built for your own camera(s), you can do them yourself. Several products support this DIY process: X-Rite provides references and software, they are probably the most popular and can create .dcp and .icc profiles.

Merci, c’est clair.

@DENISLEGROS , @platypus

Thank you for bringing this up and the explanation.
I finally gave XRite’s Colorchecker Passport 2 & software a try, BUT …

In PL4FileExport image for ICC profile there is the choice to Export as linear Raw …
or to Export as realistic color rendering …

Screen Shot 05-07-21 at 04.04 PM

As a result, I get a linear/realistic.tif, which then I can import in Colorchecker software to obtain an equivalent profile linear/realistic.icm

Screen Shot 05-07-21 at 04.03 PM

But now, instead of being able to import this profile in PL4 → Color Rendering → ICC profile

Screen Shot 05-08-21 at 12.12 AM

I get the message to choose a RGB profile,

Screen Shot 05-07-21 at 04.09 PM

while the ICC Profile Inspector indicates the linear/realistic.icm to be an ‘Input RGB file’.

To see, if the export menue is ‘broken’, I also exported the pic directly as NoCorrection.tif …,
but again no success.

Screen Shot 05-08-21 at 01.47 AM

BUT, what worked …

  • in PL4, I generated a DNG-file (without any corrections, exported as ‘DNG Denoise & opt. Corrections only’),
  • passed it to Colorchecker software to produce a *.dcp camera profile,
  • successfully imported it in PL4,
  • to finally obtain an image corrected with my own camera’s profile.

The same worked from / within LR 5 via the Colorchecker plugin (DxO-DNG / NEF). *)

Now my question, should PL4FileExport image for ICC profileExport as linear Raw … produce DNG-files instead of TIF or has it a problem to import ICC/ICM-camera-profiles? *)


@StevenL, could you please pass this on to someone at DxO staff? It seems like a bug.

edit *)

1 Like

I was not aware that this is even possible, what a cool idea. Whereby, not exactly cheap. I’m usually fiddling around with HSL tool and store tonal corrections in my presets. Works, but is a lot of trial-and-error-work…

Hi Wolfgang,
Thanks for your detailed investigation: we have effectively found a bug!
It will be fixed in the coming weeks. Stay tuned…



J’ai un doute, les profils créés avec un Colorchecker en exportant une RAW linéaire seraient-ils un standard valable pour le modèle de caméra ou seulement pour le modèle de caméra dans certaines conditions d’éclairage ?
D’autre part, dois-je désactiver toutes les corrections que PhotoLab applique à l’image ou l’exportation ne les prendrait pas en compte ?
Merci !

@vichenso, color checker profiles can be created as dual-illuminant profiles to cover a wider range of lighting conditions. They can be used for very specific lighting conditions too.

Whatever profile we use, PhotoLab has an idea of how an image should look, which means that we still have to change (correct) things to make the image look like we want it to look. Once we get what we like, we’ll export without deactivating settings. Exported files might still be different from what we saw on our screen. If we use a dark screen to set the image, the exported image will look differently if viewed on a bright background. Our brain does many things with our perception under different lighting, that’s why lighting is so important.