Ensure print-friendly colors with the Photoshop Gamut Warning

How to use the Photoshop Gamut Warning

Photoshop Gamut Warning: before Photoshop Gamut Warning: after

Your computer mixes Red, Green and Blue (RGB) channels together to produce millions of different colours. Printers combine Cyan, Magenta, Yellow and Black (CMYK) inks to create a more limited colour palette. On-screen colours that can’t be reproduced in print are called ‘out of gamut’ (or out of range) colours.

Although Elements users can produce more print-friendly colours using the Adobe RGB colour space, you can still boost colour saturation to accurately reproduce them.

Photoshop CS users have tools to help them keep edited colours within a printable range, like the CMYK mode and an out-of-gamut warning. Here, we’ll show you how to use these more advanced CS tools.

Photoshop Gamut Warning: choose a color space

Step 1: Choose a colour space
Photoshop CS users can follow steps 1 to 4 in the main walkthrough to tweak the start image in CS’s Camera Raw editor. Once you’ve clicked Open Image, go to Edit>Colour Settings. In Working Spaces, set the RGB menu to Adobe RGB (1998) to work in a printer-friendly colour space. Click OK.

Photoshop Gamut Warning: tick gamut warning

Step 2: Gamut Warning
Add a Hue/Saturation Adjustment Layer, boost the Blues Saturation to +57 and set Hue to +20. Go to Window and tick Gamut Warning. Most of the sky will turn a patchy grey, indicating these colours are out of a printer’s range. Drop the Blues Saturation down to +35 to reduce the gamut warning patches.

Photoshop Gamut Warning: edit the mask

Step 3: Edit the mask
Follow steps 7 to 9 to boost the colour saturation of the Cyans, Reds and Yellows. This will add more gamut warning patches to parts of the scene. You can reduce the intensity of the colour saturation by dropping the Adjustment Layer’s Opacity to 80%.

Photoshop Gamut Warning: change mode

Step 4: Change mode
To force Photoshop CS to use printer-friendly colours go to Image>Mode>CMYK Colour. Click Flatten, then OK to choose a CMYK profile. The gamut warning patches will vanish, and the colours 
on screen will be more similar to those in print.


99 common photography problems (and how to solve them)
10 rules of photo composition (and why they work)
See the light like a pro: everything you were afraid to ask about natural light