How can I correctly display CMYK images in Viewer and Slideshow?

DavidOfMA · July 15, 2014, 03:24:43 PM

CMYK images show up with distorted colors in the Viewer and Slideshow. I have turned on Color Management in Edit-Preferences-Application for the Viewer, don't see anywhere to turn it on for the slideshow, but in any case the colors of my CMYK files are being displayed as if they were sRGB.

The files have the correct colors in the Thumbnail view and in Faststone Image Viewer (as well, of course, as Photoshop). How can I get them to display correctly in IMatch?

Thanks,
Davide

Mario · July 15, 2014, 04:31:59 PM

CYMK is always troublesome. It's for print, not for screen, and support in the image libraries I use is limited.
Send me a sample file so I can run some tests. the CMYK files I have look rather OK.

DavidOfMA · July 15, 2014, 05:20:08 PM

I understand they are for print - these images are part of a book I'm writing - but it would still be nice to be able to view them in IMatch as they look in Photoshop or Faststone. I'll send you a sample image when I get home tonight. My recollection is that they looked fine in IMatch 3 and they look fine in the thumbnails in IMatch 5, so some part of IMatch 5 "understands" how to display them.

Mario · July 15, 2014, 07:17:43 PM

Thumbnails by default do not apply color profiles, but the Viewer does. Maybe this is the reason?

DavidOfMA · July 15, 2014, 08:06:08 PM

I 'll have to look at it when I get home. My recollection is that I turned color management on everywhere I could, and that it worked with the thumbnails, didn't work with the Viewer, and didn't seem possible to do with the Slideshow. My personal preference is to have it turned on everywhere so I don't have to resort to a different program to see the color-managed colors. Even with a slow computer, I didn't notice much difference in display speed with it on or off.

Mario · July 15, 2014, 08:16:40 PM

Slide show is color managed.

DavidOfMA · July 15, 2014, 08:38:20 PM

That's good to know.

Mario · July 16, 2014, 12:06:15 AM

IMatch is color management, except for thumbnails. Here color management is optional because it causes a serious performance hit.

DavidOfMA · July 16, 2014, 03:44:24 AM

I sent you a CMYK image that illustrates the problem, as well as some screen shots that show what it is supposed to look like and what it and another image (that is monochrome) look like in the Viewer. Hope this helps fix the problem.

David

sinus · July 16, 2014, 11:25:02 AM

Quote from: DavidOfMA on July 16, 2014, 03:44:24 AM
I sent you a CMYK image that illustrates the problem, as well as some screen shots that show what it is supposed to look like and what it and another image (that is monochrome) look like in the Viewer. Hope this helps fix the problem.

David

OT: just because it interesses me: where or why do you work with CMYK and not RGB? Some years ago I had also to "fiddle" with CMYK, but nowadays I print Books or deliver images allways in RGB. I guess, you are on the end of the workflow for a book, and there an image is maybe in CMYK or must be.

DavidOfMA · July 16, 2014, 02:31:00 PM

Hi, Markus. I'm doing a book, and the printer wants the images in CMYK. I've never had to do the conversion with other books, but actually I'm glad I did, as some of the images are way out of CMYK gamut, and I had to tinker with them quite a bit to make them look more or less as they should.

sinus · July 16, 2014, 03:55:58 PM

Quote from: DavidOfMA on July 16, 2014, 02:31:00 PM
Hi, Markus. I'm doing a book, and the printer wants the images in CMYK. I've never had to do the conversion with other books, but actually I'm glad I did, as some of the images are way out of CMYK gamut, and I had to tinker with them quite a bit to make them look more or less as they should.

Ah, thanks for your response, David.
I see, if the printer wants the images in CMYK (what is here in Switzerland possible, but usually the printer or the print-company can handle both RGB and CMYK), than this explains your workflow.

Hope, your book will finally end as a very good result.

Mario · July 29, 2014, 02:05:47 PM

I could improve treatment of CYMK files substantially by supplying and applying a custom CYMK conversion profile. This will be part of 5.1.12.
If you use cache files, you will have to re-create cache files. For JPEG files, no cache is used by default so the change will be immediately visible.

DavidOfMA · August 03, 2014, 12:53:53 AM

That would be great! Looking forward to 5.1.12 for this and the background processing changes.

Thanks,
David