Photoshop® CS4 Bible

15.4. Summary

This chapter described ways you can correct the color of images, change colors in images, and add colors to images. Following are key concepts:

• Some images have an undesirable color cast (an undesirable color tint) that needs to be corrected.

• Before you start color-correcting an image, it's a good idea to do the following:

  • Check the image size and resolution.

  • Consider working on a larger master file with preserved layers.

  • Think about correcting full-color images in RGB or Lab color mode.

  • Set Photoshop's Color Settings appropriately.

  • Create a soft-proof profile so you can proof the image on-screen as you work.

  • Calibrate your monitor.

• A good approach to color correction involves changing color numbers that represent the colors in an image to known color-number values (memory colors), such as those for neutral-colored areas, green foliage, blue sky, and flesh tones. When you change known colors to the values they should be, the other colors in the image often adjust proportionately to the correct colors.

• You can measure colors in an image by sampling them with the Eyedropper tool and/or the Color Sampler tool and observing the color numbers in the Info palette. Before-adjustments and after-adjustments numbers are separated by a slash in the Info palette.

• A common way to change color numbers is by using the White Point, Gray Point, and Black Point eyedroppers in a Curves adjustment layer dialog box to set neutral colors to what they should be and by adjusting the curves in a Curves ...