Converting to CMYK doesn't change screen color

[Djuna_A_]

Hi there,

I am illustrating a book, and the publisher has requested PSD files in CMYK.  My original files are TIF.  When I convert from RGB to CMYK either as a TIF or PSD file, I don't see the typical color change on my screen, which is too good to be true.  Any ideas? 

Thanks!

[gener7 · Accepted solution]

Maybe the colors are already in the CMYK range despite being RGB mode.

"Proofing" is one way to know.

First go to View > Proof Setup and select "Working CMYK" which in my case is US Web Coated Swop v 2

If he has a custom profile for his press, select that in Proof Setup after you load it.

Then with your RGB Image open, Ctrl or Cmd Y to simulate what it looks like when you convert to CMYK.

If you are still in doubt, see a print shop about having a proof copy made.

[Djuna_A_]

Thank you thank you!

[Djuna_A_]

it seems that that function is disabled once the file is converted to a specific profile, is that right? (Edit > Convert to Profile > Japan Color 2001 Coated)

[gener7]

No, Proofing is not disabled. You just won't see much difference between a CMYK profile and a CMYK proof representing  that profile.

Look at your file tab. CMYK/8 is your file and when you try cmd/ctrl Y, /US WebCoated indicated it is being proofed to that profile.

[c.pfaffenbichler]

Then with your RGB Image open, Ctrl or Cmd Y to simulate what it looks like when you convert to CMYK.

And View > Gamut Warning will similarly indicate the RGB image’s out-of-gamut regions with an overlay (according to the last Proof Setup).

[leiac40700920]

Hello,

I actually have the same problem and wanted to ask you again if I got right what you said there..

I made an illustration I want to get printed. I worked on it in RGB mode and because it gets printed I want to convert it to CMYK to make sure it still looks nicely when printed.

So as said,

I am currently on RGB mode (when I change to CMYK mode the colors don't change, wich they usually do, and always did when I tried it before)
My color proof setup is set at CMYK
And when I do cmd + y (color proof) the colors are not changing either

Does that mean I have already been working with CMYK Colors without knowing it despite being in RGB mode and I don't have to change anything for printing?

If so, theres still something I don't get. Wich is that when I got a test print and it looked completely different from what my photoshop showed me it would look like (trying from RGB mode and CMYK mode). I hope you can help me 😞

[D Fosse]

Is this going to an offset press? If not you should stay in RGB. Inkjet printers work with RGB data.

You only see a difference if there are colors that are out of gamut in the destination color space, and at the same time within monitor gamut. 

There's not supposed to be a general color shift.

[c.pfaffenbichler]

I worked on it in RGB mode

But what is the actual RGB Colour Space?

Is the profile embedded in the image?

Please set the Status Bar to »Document Profile« and post more meaningful screenshots.

My color proof setup is set at CMYK

Which CMYK?

[c.pfaffenbichler]

Just to make sure: Did the printer tell you the actually printed CMYK Color Space?

What was the RGB images’ original Color Space?

Do the RGB images feature highly saturated colors at all?

[Djuna_A_]

No, they didn't.  I don't know what Color Space is.  The colors are moderately saturated.  Sometimes in CMYK, I see areas of "peeling," which I assume are the saturated areas...

[gener7]

A "color space" is the range of colors that a device will produce. A "device profile" tells Photoshop what that range is, so that the Adobe Color Manager can correctly convert your colors.

Here is a primer: http://clickitupanotch.com/2016/09/color-space-questions-srgb-vs-adobe-rgb/

There's much more to learn, but basically you convert from one profile to another to to get accurate color and you make sure you have a calibrated and profiled monitor for best results. Monitors, unless they are very expensive, are sRGB profile.

Bear in mind CMYK is more limited in colors than RGB. Also ask your printer what CMYK profile he wants you to use, and if it does not ship with Photoshop, he should supply it to you. US Coated Standard Web Offset Press (SWOP) is what is called a CMYK profile, because that kind of printing press uses the Cyan, Magenta, Yelllow, and Black (K) inks to print your artwork. If the publisher uses a different press, he should tell you what profile to use or supply you with it.

[Djuna_A_]

Thanks, Gener7.

Yes, my  monitor is sRGB.  I only see the real CMYK colors when I mail files to the author.

No way I am going to learn all this...

So we've asked the publisher to do the CMYK editing. I will send them RGB printouts for reference. I was thinking that I'd flatten all the layers in each file for their convenience, but now I wonder if I should keep the layers.  Will having access to the layers facilitate their editing?

[gener7]

That's what I'm thinking. Let the publisher/printer handle the conversion to CMYK. It's quite common.

No layers. Just flatten and send as a tiff.  A flattened tiff can be read by most any software when the goal is print.

Suggested settings:

[Djuna_A_]

Even if they've requested PSD? 

[gener7]

If they request PSD, then they can take it. Tiff is for when you don't know if they can.

Normally they should have no need to edit your files, but ask. If not, flatten the file.