CHROMiX

V3.0.5 and v4 ICC printer profiles

Hello, does ColorThink v3.0.5 work correct with ICC v4 printer profiles. I mean the curves Neutral rendering Chroma is showing bluish cast and nonsense values. Profile built with i1profiler

Hi Joe,

CTP 3.0.5 should open v4 profiles fine… but, it can have white point problems on newer macOS versions.

If you’re on a Mac, try downloading the newer version available here:

CT Download Page

If you continue to have issues, please DM the profile to me and we’ll take a look

Steve

Windows here, same data v2 vs. v4
where does the b-19 in v4 come from?

The wtpt tag in the profile will specify the “White Point” values you see in the Overview tab

V2

Blockquote
XYZ: 0.8422699, 0.88346863, 0.72975159
Lab: 95.3068007, -1.8068409, -0.0617904
LCH: 95.3068007, 1.8078972, 181.9586408
Yxy: 0.8834686, 0.343015, 0.3597932
Luv: 95.3068007, 0.2069008, 0.4882974
5100B0K
Blockquote

V4

Blockquote
XYZ: 0.8422699, 0.88346863, 0.72975159
Lab: 95.3068007, -1.8068409, -0.0617904
LCH: 95.3068007, 1.8078972, 181.9586408
Yxy: 0.8834686, 0.343015, 0.3597932
Luv: 95.3068007, 0.2069008, 0.4882974
5100B0K
Blockquote

The D65 was selected for both profiles. Tags look the same. Why they are shown different, bug in Colorthink?

OK, now you have me wondering what’s going on.

Can you DM me the two profiles? I’ll take a closer look

thanks

Steve

What do you mean “DM” ? I’m unable to find how to send you PM.

Nevermind, here is the two profiles

Still waiting for reply, is the profile OK, bug in CTP or bad profile?

We’re still working on this. No firm answer yet. I do know that with version 4 profiles, the “computation steps required for the media White Point Tag were clarified in V4.” That should make version 4 profiles more trustworthy if anything. We’ll figure it out and get you an answer.

Hi Joe,

I’ve been able to confirm the problem on Windows. It’s related to the CMM used in ColorThink and some version 4 profiles.

Interestingly, it doesn’t happen in the Mac version even though the code and (in theory) the CMM are the same…

So thanks for the heads up. We’ll work on a fix

Steve