Why are you dinking with CMYK period?
Monitors are RGB devices.
Mac
The process of converting to a JPG, for example, converts from CMYK to RGB. I’m not sure why you are choosing CMYK for web unless it’s because you want a particular color. If that’s the case, CMYK isn’t the way to do it.
Also, the web and ACDSee are not color managed, photoshop is. So you are seeing a shift in an rgb image. You might want to calibrate your monitor.
Peace,
Tony
Hi Mac and Tony,
Thanks for your replies.
I need to use CMYK because I’m printing the images onto canvas, and the printing machine requires those colours. But I need to show the images on a CD-ROM as a marketting tool for potential sales outlets (and possibly a website).
I have calibrated my monitor.
So is there no way I can get CMYK colours to show outside Photoshop?
Paul
Paul,
I need to use CMYK because I’m printing the images onto canvas, and the printing machine requires those colours.
Are you printing to this "printing machine" from photoshop or is it a commercial service? If the latter, supply them with a CMYK file with the embedded color profile as a Tiff.
As far as the other, basically, you’re assuming it’s a CMYK/RGB shift when in fact, it may be a color management issue. From what I read in your post, you don’t need CMYK for showing potential clients, you just need those colors represented. For printing you do, but for viewing, no.
The CMYK Gamut is smaller than RGB, and while SOME RGB colors lie outside that gamut, most will be in. So what you want is an accurate representation of the color when viewed by others – that is, if I understand correctly.
So the remedy is: Calibrate everyone’s monitor who will view the image, or, live with the idea that there are some things you can’t control, like, how your images will be displayed on other people’s monitors.
Oh, you can get close. What *I* do, and I’m not saying it’s the most sage approach, just that it seems to work, is the following. I use an sRGB color space and have a calibrated monitor. Give or take, the images I produce reasonably well, within a certain margin across the board. BUT… take it to an LCD screen and they’re all washed out.
If I bring a color managed image into a color managed application, no problems. But the web, and (AFAIK) most Microsoft products are NOT color managed; neither is ACDSee. So they’re going to see generic – no profile.
So you’re best off, IMO, creating two images: one for print output with the CMYK Colors (provide as a tiff for example) and one that represents those colors well when you turn color management off in photoshop, or, if you’re lucky, use sRGB as a color space and hope for the best.
Peace,
Tony
Paul,
So is there no way I can get CMYK colours to show outside Photoshop?<<
No, you can only show an RGB representation of your CMYK files in most applications and particularly on the web. Very few applications can display CMYK data.
One method you MAY be able to use is to save your files as PDF. Acrobat should give a reasonable representation of the file data
Well, now I’m confused, where did the rest of my post go?
I was going to say something to the effect of
Paul,
You have to repurpose your images, in other words, you will have different files depending on what you are doing at the moment with your image.
You should always keep a high-res RGB "master" copy somewhere though
No, you can only show an RGB representation of your CMYK files in most applications and particularly on the web.
I would amend that to say "No, you can only show an RGB representation of your CMYK files in all applications and particularly on the web. Considering a display from an application is bound to be on a monitor which uses RGB phosphors.
Very few applications can display CMYK data.
….and those that do, convert to RGB to do it.
Converting from CMYK to ANY RGB space should maintain all your colors, given that you are going into a larger color space from a smaller one. (OK, well maybe not 100% Cyan to some smaller gamut RGB spaces but the difference is not objectionable)
Thanks everyone for your suggestions.
All I’m trying to do is represent the CMYK colours on a website/CD-ROM. The images themselves don’t need ot be CMYK, but the colours need to represent the CMYK colours. I’ve since discovered that by transferring the CMYK files back to RGB, then saving them will keep the old CMYK shades, albeit in an RGB file.
I appreciate everyone’s advise. I’ve learned a lot!
Cheers,
Paul
Paul
I would be interested in knowing what colors in your image are changing when you go from cmyk to rgb. As Tony noted, there is usually quite a shift going from rgb to cmyk, but seldom one going the other way.
Only a small range of cmyk colors are not available in rgb, and they are only slightly out of gamut, usually not enough to be noticed.
Don