Offender - Photoshop CS5
I tell a vector layer to be 100% Cyan, 0% Magenta, Yellow and Black (by double-clicking the Layer Panel thumbnail and punching in values).
I hit enter. Then I go back into it's color dialogue and I see that it's automatically changed to something like 70% Cyan, 15% Magenta, 0% Yellow, Black.
What the heck.
Assigned a new color profile - Abobe RGB '98. Got it closer. Still not happy. I want that process printer to know to use 100% for that part of the design.
I don't want no stinkin' Magenter in meh Cyan!! Why, Photoshop? Why.
It may be odd that I design in RGB, just to convert to CMYK in order to produce the final production file but I design with this in mind, always keeping an eye on Out Of Gamut pixels, etc. Seems to work well.
Would you say you disagree with my MO, in this case then?
As you know, all RGB-based effects, adjustments, filters are unavailable in CMYK mode, which has caused me to avoid actually working in CMYK.
I'll usually complete a design, flatten, do a strategic CMYK conversion, then save a flat TIFF for production. As long as I'm mindful that everything will be processed-printed I do ok . . . I think.
Also are you certain your CMYK working space is the proper CMYK-space for this printing process?
No. To be honest, I'm very confused by the CMYK options.
My current project is a series of posters all to be printed on an HP 25500 wide format printer. What should I do? I only use the default "U.S.Web Coated (SWOP) v2" profile.
In general editing photographic images in RGB even when printed CMYK makes complete sense.
But with graphical elements that are supposed to have one or two process colors – it’s just a bit risky not doing those in CMYK (unless one has an »airtight« device link profile set up for the task, I guess).
Either you should ask your print provider for a profile for the printer
or – as it seems to be a six color printer – you (and me) may be overthinking it and you providing an RGB image may turn out just fine.
In any case it might be best to check qith your print-shop.
Hehe, the print shop is 30 feet away. I'm an in-houser. We got a very experienced, old-school, plate-maker guy, from the haftone camera era, running the printer. He's not up on color profiles, though. I've already asked him.
I will try to get a color profile to use for previewing, inside Photoshop.
Right now, I've asked him to print a RGB and CMYK version of the same thing. I want to do a visual comparison of the two outputs.
Hey . . . so we can convert file to 4 color "CMYK" in PS, but is converting files to a 6-color process a thing? The HP has Light Cyan and Light Magenta, in addition to C, M, Y and K. Why not convert the file to the printer 6-color processing, for even more accurate pre-flighting?
In addition to #6 C.Pfaffenbichler as well
For large format inkjets it's not recommended to edit in CMYK.
One uses just sRGB or AdobeRGB(98) and
a) embeds the profile or
b) tells the printer operator the color space explicitly
Yellow, Magenta, Light Magenta, Cyan, Light Cyan, Black and
eventuallyDark Gray and Light Gray are handled by the RIP.
Thinking in "plates" is of no use. Converted to CMYK, one would
have just four channels, but eight different inks.
If a valid profile should be available, then it would be quite useful
for Soft Proofing, which might help to avoid making ordinary apples
Best regards --Gernot Hoffmann
Europe, Middle East and Africa