On 22 Aug 2018, at 21:00, Andreas Kraushaar <andreas.kraushaar@gmx.de> wrote:
this is a „problem“ or a „feature" with ICC based white point scaling (required for colorimetrical encoding of data). Rendering neutrals from ab=0,0 to ab=2,5 -10 is quite a change and XYZ-scaling from black to white does not reflect the required XYZ to be printed to actually get a decent print. The solution would be to use a perceptual rendering intent that does a grey mapping close to ab=0,0 and not to what XYZ scaling predicts. I know many color server device link profiles (F39 - F52 and also ECI-RGB to F52) that does this job.
Andreas It’s not us who have the problem — it is everybody who uses Photoshop with RelCol +BPC to do the conversions :( This is a common choice because, for most images, they see very little difference between the RGB and CMYK versions of their images in Photoshop. But on proof and on press it then becomes our problem. -- Martin Orpen Idea Digital Imaging Ltd