Discover the intricacies of CMYK conversions in Photoshop, including how to choose the correct profile for your conversion, load color profiles, compare different conversions, and understand the importance of these profiles in creating accurate colors for your designs and images.
This exercise is excerpted from Noble Desktop’s past Photoshop training materials and is compatible with Photoshop updates through 2020. To learn current skills in Photoshop, check out our Photoshop Bootcamp and graphic design classes in NYC and live online.
Note: These materials are provided to give prospective students a sense of how we structure our class exercises and supplementary materials. During the course, you will get access to the accompanying class files, live instructor demonstrations, and hands-on instruction.
Topics covered in this Photoshop tutorial:
Converting to CMYK, Loading color profiles, Comparing different CMYK conversions
Exercise Preview
Exercise Overview
Choosing the correct profile for your conversion to CMYK is an oft-neglected but very important step. Here we’ll compare some profiles to see just how different—and important—they really are.
Getting Started
Close all files you may have open, then open yourname-lifestyle.psd.
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In the dialog make sure Use the embedded profile is chosen and click OK.
Explanation: This image’s embedded profile is ColorMatch RGB. Like Adobe RGB, ColorMatch RGB is a good, device-independent workspace. Even though in this class we’ve chosen Adobe RGB as our workspace, it’s not worth converting from one to the other because loss can occur when converting between colorspaces. Because ColorMatch RGB is a perfectly good workspace, we should just use it for this image.
Save the file as yourname-lifestyle-flat4printer.psd.
Go to Layer > Flatten Image.
Checking for Profiles
When dealing with printers, you will hopefully be able to get a profile from them which describes their press/paper. You’ll need to load the profile onto your computer to use it in Photoshop. We’re going to use two color profiles that you may not have on your computer. To check to see if you have them, go to Edit > Color Settings.
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Under Working Spaces, go to the CMYK menu and see if the following are listed:
- Light GCR 280 UCR CMYK US Negative Proofing
- Light GCR 360 UCR CMYK US Negative Proofing
Cancel out of this dialog. If they are listed, skip over the next section (Loading Extra Profiles) and continue on. If they are not listed, do the next section.
Loading Extra Profiles
Hide or minimize Photoshop so you can see the Desktop.
Go into Class Files > Photoshop Adv Class, then the extra_profiles folder.
Hit Cmd–A (Mac) or Ctrl–A (Windows) to select the two files.
Hit Cmd–C (Mac) or Ctrl–C (Windows) to copy them.
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The location you need to paste the profiles in depends on your operating system:
Mac Users
Hold Opt and from the Go menu choose Library.
Navigate into ColorSync > Profiles.
- Once you’re in the Profiles folder, hit Cmd–V to paste the two files into it.
Windows Users
Navigate into C: drive, then into Windows > System 32 > spool > drivers > color.
- Once you’re in the color folder, hit Ctrl–V to paste the two files into it.
Return to Photoshop and proceed to the next section.
Making a Copy so We Can Compare the Settings
To duplicate the image, go to Image > Duplicate and click OK. You should now have two copies of the image open, making it easy to compare.
Go to Window > Arrange > 2-up Vertical
.In one window pane, Zoom out a bit so that you can see most of the image.
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Go to Window > Arrange > Match All. Your screen should look similar to the one shown below. This makes comparing the images easy.
Applying the Settings & Converting to CMYK
We’re going to convert each of the images to CMYK using different settings. Let’s start with the image on the left. Click on it to make sure it’s active.
Go to Edit > Color Settings.
Under Working Spaces, from the CMYK menu, choose U.S. Web Coated (SWOP) v2.
Click OK.
Now do the CMYK conversion by going into Image > Mode > CMYK Color.
If you get a message about profiles, check Don’t show again and click OK.
Click on the image on the right to make sure it’s active.
Go to Edit > Color Settings.
Under Working Spaces, from the CMYK menu, choose Light GCR 360 UCR CMYK US Negative Proofing.
Click OK.
Go to Image > Mode > CMYK Color.
Comparing Differences Between the Conversions
Now that both files are converted to CMYK, look for any differences. Ideally we shouldn’t see too much of a difference when looking at the final CMYK composite image. Where we’ll see more differences is in the individual channels.
Let’s look more closely. One at a time, select an image and then view only the Cyan channel, so both images are showing the Cyan channel. Compare the differences between the images. Choosing different CMYK profiles affects how RGB images are separated into CMYK. Look especially at the dark areas of the jeans.
One at a time, select an image and view only the Magenta channel, so both images are showing the Magenta channel. Compare the differences.
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Repeat this for the Yellow and Black channels to see their differences.
Wow! Some of them are quite different. Now you can really see how choosing the correct CMYK profile based on your output device can create the right separations/color specifically for that device!
When done, close both files without saving changes.