Does soft-proofing work without looking to the output profile?

[Morgan_Hardwood]

@Hombre

According to your comment (and extrapolated), RT should convert from CIELab to the Working Space, then the Output profile, then the Printer profile, then the monitor Profile (some of them done by LCMS). Am I right ?

This makes sense to me.

@Hombre

The Working space should also be optional, because some output profile (like ‘aces’) are wider than all the proposed Working space (I suppose). We should offer ‘aces’ as working profile, but that not planned.

I opened issues for DCI-P3 and ACES inclusion:

Add DCI-P3 output color profile

Add ACES color profile

@Hombre

So basically what you’re asking for is using the soft-proofing feature to simulate the output profile and not any printer profile ? And the possibility to cumulate both ? I could add a second “soft-proof” button next to the existing one. The first one would be for the output profile, the second one would be for the printer profile. I don’t think we’ll be able to ask for out of gamut pixels for both profiles. If both buttons are pressed, you’ll have the printer profile gamut, otherwise the gamut of the pressed button (i.e. output profile OR printer profile).

I see two common use cases, and I will not use the word “proof” to avoid the semantic politics:

1. User wants to see what the image will directly look like if it gets saved using some output color space and rendering intent,
   e.g. sRGB/perceptual (squashing all the colors into sRGB).
   e.g. JapanColor2003WebCoated.icc/relative colorimetric.
   The output color space could be a printer color space.
   The color pipeline would be:
   RT working space > RT ouput space (could be printer) > Monitor profile
2. User wants to see what the image will look like if it gets saved using some output color space and rendering intent and then subsequently will be printed.
   e.g. saved to sRGB then sent to a printer which uses JapanColor2003WebCoated.icc/relative colorimetric.
   The output color space would not be a printer color space.
   The color pipeline would be:
   RT working space > RT output space (not printer) > RT printer space > Monitor profile

Basically step 2 is a shortcut so one does not have to save the raw image first to TIFF using a typical output space like sRGB and then having to open the TIFF and set the printer space as output and view what that would look like.

@Elle

The RT-provided output profiles (used to - still?) have point TRCs, which automatically clip upon conversion even at floating point, and of course clip upon exporting to disk at integer precision. I don’t know what RT uses as the equivalent internal working spaces - do the built-in working spaces use point curve TRCs?

@jdc might know.

@Elle

“here is some code that answers some specific soft proofing problems, and maybe RT might benefit from incorporating similar code”. Personally I would like to see the same sort of code incorporated into GIMP. I’d like to see the same functionality in all free/libre image editing software because soft proofing is an essential part of image editing work flows.

@Hombre

Doing what you’re asking for require a CMM tab next to the History panel. That was planned but not started yet.

Monitor profile, rendering intent and soft-proofing tab