ecoecho Posted June 24, 2019 Share Posted June 24, 2019 Hello, Using Publisher, I have been testing PDF output (X-4) in a CYMK color space using 16 bit RGB images (sRGB profile) and not all of the photos render correctly. Some of my layouts are grids of 36 images, and over half will render with reversed colors (yellows are magenta). I cannot find any differences between the RGB files that convert correctly that those that don’t. If I convert those images to CYMK in PS, the colors of those images will render correctly. If I export as PDF/X-3 2003 they all render correctly. (This is RGB). What could be the difference within these 16bit sRGB Tiff files? They do originate from different cameras. That should not make a difference. If I convert to 8 bit, this seems to correct the problem. Conversely, for such dense image layouts, (36 and 49 per spread) perhaps I should convert to CYMK as an extra proofing fail safe? Thanks in advance for any advice. RT Simon Quote Link to comment Share on other sites More sharing options...
Staff stokerg Posted June 27, 2019 Staff Share Posted June 27, 2019 Hi echoecho, Can you attach a couple of sample images, one from each camera so i can look into this? There must be some difference between the images, otherwise i can't see why this would be an issue Quote Link to comment Share on other sites More sharing options...
ecoecho Posted July 3, 2019 Author Share Posted July 3, 2019 Hi stokerg, Please excuse the late reply. This colour anomaly was happening with RAW files from the same camera session. They were all exported from Lightroom at the same time with an sRGB profile. I have one layout that contains 49 images in a grid, taken all at the same event, and only the top seven images were being shown correctly and a few others, with most reversed (yellow is purple). This is not on screen in Publisher, only in a CYMK PDF. I needed to start proofing so stumbled on a quick fix. Enter Affinty Photo from within Publisher, and apply any filter with zero value (no change is made to the photo). (Sometimes the images can use a little correction anyway.) This corrects the color when outputting a CYMK PDF. I have an Epson 7880 printer which is profiled for a semi matte proofing paper. Screen colour to paper colour is identical. No problem in my own printing environment. What don’t I understand: When Affinity Photo correction filters are applied, the original file is not overwritten. So it is the PDF that is storing the adjustments to the original. (Or in this case, a ZERO-value filter). Fine, that works in my own setup, but how does this translate to real world commercial printing? I would think the original files need to be overwritten with ANY correction as a commercial printer may want to refer to the original files. I realize that even though my color management is configured correctly, it does not necessarily reflect how that same PDF colour will be printed by a commercial printer. Heaven forbid, the same anomaly occurs at that level. This is all still working with 16 bit images. I was also wondering if Publisher can compile all image files into a deliverable package, prepared for a commercial printer. Thanks for expressing interest in this matter. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.