A gamut is the range of colors that a color system can display or print. A color that can be displayed in RGB may be out of gamut, and therefore unprintable, for your CMYK setting.

In RGB mode, you can tell whether a color is out of gamut in the following ways:

• In the Info palette, an exclamation point appears next to the CMYK values whenever you move the pointer over an out‑of‑gamut color.

• In both the Color Picker and the Color palette, an alert triangle  appears. When you select an out‑of‑gamut color, the closest CMYK equivalent is displayed. To select the CMYK equivalent, click the triangle or the color patch.

  Photoshop automatically brings all colors into gamut when you convert an RGB image to CMYK. You may prefer to identify the out‑of‑gamut colors in an image or correct them manually before converting to CMYK. You can use the Gamut Warning command to highlight out‑of‑gamut colors.