Question for the Photoshop Pro's regarding CYMK

[grndfx]

Hi everyone.

Been a photgrapher for years, and worked in the digital imaging realm for quite a while now - but have a situation that I just cant figure out.

I recently had to create a design layout in Pagemaker for one of our customers, using a mixture of images, text and graphics . The images were shot in the studio using a 20D.

Now here's where it starts getting wierd.

The images were opened in Photshop and various retouching, etc was done. The finsihed image was then converted from RGB into CYMK so that it could be placed in the Pagemaker layout and sent to be printed. Whilst the image file is open in Photoshop, I can switch from RBG to CYMK and back again, and see no difference in the image (Even toggleing crtl-Y to show proof preview shows no difference) - but when I actually save the CYMK version of the file, the saved file changes and looks completely different.

I know a CYMK file will print differently on a four color press than a RGB file on an inkjet, but why does the CYMK file appear exactly the same as the RGB file when opened in Photoshop, but completly different when viewed elsewhere. I can even open both versions of the image file together in Photoshop and tile them next to each other and see no difference, but when I place both versions into the Pagemaker layout, there is a dramatic difference between the two - the CYMK versions' color appears over saturated and more contrasty overall.

The resulting problem is that we cant get the CYMK layout proofs to match the proofs based on the RGB files - even though the editing softwhere being used for the color correction (Photoshop) displays the correct color and tone. How are you supposed to do any color correction work for CYMK files when the saved file changes from the opened file?

Were tried using various color workspaces for the RGB files, but it doesn't seem to make any real difference. Each time we save the CYMK version, the resulting saved file changes its' appearance.

It got us totally puzzled - a file that looks perfect when open in Photoshop, looks completly different when opened elsewhere.

I know it must be something so simple, but I just can't figure it out. The files are all being saved as '.tiff' by the way.

Any suggestions would be greatly appriciated.

[cricket]

That is interesting...

What I do is work in RGB (Adobe 1998) and use the CMYK preview mode.

Not seeing the differences in your RGB and CMYK proofs, I'll just guess.

RGB has a much wider gamut than CMYK. That is one reason to always use the CMYK preview mode with RGB files to see how your colors are reproducing (on screen, to start).

One think to know about CMYK mode is that it often needs to be exaggerated a bit in terms of density, and to a lesser degree, color. I make my CMYK images darker, and a bit more saturated so they will print correctly.

Also, are you using any color management software such as Compass pro, or the like?

What are you proofing on, and is the printer profile in line with what you are going to get from the press? Are you going to offset, or other?

There are several variables involved! One thing I never do: I never bring a RGB image into Photoshop and convert it to CMYK mode, My CMS software does that, and I noticed that this changes the image. But, if I am working on an image that is already CMYK, I will usually leave it that way, but it's not as critical.

I use Quark and InDesign, as well as PageMaker, and the way the program treats the previews is different depending on the color mode you are placing in the program. The CMYK images always look strange as you described. But so do the RGB ones after the CMS software converts them.

If you must convert the image to CMYK, then make sur eyou have the printer's profile and do tests with the printer as the proofing printer you use may be quite different than what the Printer produces for you.

Well, not having more details, that's all I can think of off the top of my head. However, if you have any questions you want answered, I could ask the press folks at work (I'm a Graphic Designer) and they might be able to help!

Good Luck!

[grndfx]

Thanks for your input, cricket. You brought up some good thoughts.

Strangely I'm seeing the opposite in my saved CYMK images to you. The image appears darker and more saturated and I would have to lighten them and desaturate a little to get it to print correctly.

I'm doing some basic inhouse proofing on an S9000, not for strict color balance but mainly for design & layout testing. We recieved an intitial proof from the printers yesterday, and although their results were not as far off as our S9000 proofs, the images still differed noticably from the CYMK version when it opens in Photoshop.

The main query I have is not so much whether it is color correct in CYMK mode to the printers proofs, but rather why Photoshop displays both image modes (RBG & CYMK) as being the same in appearance, when other programs show them differently.

Here's a little test to try - I'd be curious of other peoples results.

Open an image file in Photoshop and without doing anything else, just convert it to CYMK. Does it look the same? If so, save this new CYMK version back to the same folder as the original (use a different file name so as not to save over the original). Now go to your folder with the two files and look at them both outside of Photoshop (I use ACDsee or Pagemaker, but any program should do. )

Do they both still look the same? If they do, then congratulations - I wish mine did.

If not, they why not. Thats' what I dont understand. They were both the same a minute ago in Photoshop.

If they are both looking different, try opening them both up in Photoshop and 'tile' them next to each other. Do they still look different now, or are they the same again. If they look the same, then what happens to the CYMK file when it opens in Photoshop to make it look like the RGB file again. And can it be turned off?

I've tried this test using both an Adobe 1998 colorspace and sRGB colorspace and yet the saved CYMK file still appears differently from the original RGB file when viewed outside of Photoshop.

The printer says he can do some color correction when it goes to print, so that the images appear as we intend. But It would be nice to be able to view a CYMK file in Photoshop the same as my other software views it.

I know these are some long posts, and I thank everyone for checking them out.

[ecobo]

ACDsee do not display CMYK colors correctly. It is just made for RGB colors. Versions before and incl. v.5 can represent only sRGB colors. The new v.7 can be set to display any RGB color space, but not CMYK.
I don't know why you are using PageMaker. It's a crap. I dont want to frighten you, but you will probably have other mismatchings - fonts, text position, overprints etc.
PageMaker uses the Windows display system - you will see the same as with ACDsee.
I use Photoshop, Illustrator and InDesign - a very well build combination. InDesign has his own display system that matches perfectly with Photoshop and Illustrator. I see the same with these three programs and the offset printed output matches perfectly the colors on my monitor. I use a ColorVision Spyder2PRO to calibrate my monitors.
Do not care about the colors you see in PageMaker. If they are correct in Photoshop, it's OK. You got to make all the corrections (levels, curves, HS etc.) in RGB mode, 48bit color is recommended. After completing all the work, save a copy of your RGB file, convert it to CMYK and apply an USM filter. If you need some additional corrections, do them in the RGB file, not the CMYK one.
I recommend to save the CMYK files in DCS format. In PageMaker it works very well and speeds-up the color separation process. Do not use DCS in InDesign if you plan to use special effects as drop shadows and feater over the DCS image as the DCS is an EPS (locked) file.