Range: Used with the Dodge and Burn tools, this allows you to select a tonal range to lighten or darken (midtones, highlights, or shadows).
Raster data: This data is defined by its colors and pixels and is not defined mathematically. Digital pictures are raster data. Some tools in Photoshop can only be applied to raster data or raster images.
Rasterize: Converting vector data to raster data. Performing this conversion is called rasterizing.
Registration marks: When printing, these marks are used to print marks on the image for alignment on the press (bull’s-eyes and star targets).
Reproduction Proofs: Often camera-ready artwork. These proofs are used to reproduce an image or print.
Resolution: Resolution determines how many pixels are shown per unit (such as inch or centimeter) in an image. Higher resolutions contain more pixels (thus more detail) than lower resolution images.
Reversal Processing: The process in which film is exposed so that it will become a positive instead of a negative or a negative instead of a positive.
Reverse: Reverses the chosen gradient’s colors. Used with the Gradient tool.
Revert: Located in the File menu, the Revert command returns the file to the condition it was in the last time it was saved.
RGB mode: A color mode that uses red, green, and blue to create the colors you see. Monitors use RGB mode to output color, and RGB mode is Photoshop’s default.
RIP (Raster Image Processor): A processor (like a CPU) included in an output device that converts an image’s data into the dot pattern. It is this dot pattern that is printed onto film or paper.
Roman Type: A regular version of a font, versus bold or italic.
Rotate: A Transform tool that allows you to rotate an object around its center point. The center point can be changed.
Roundness: Controls how round the brush stroke will be. A setting of 100 percent creates a circular brush stroke; 0 percent creates a linear brush stroke.
Rules: Vertical or horizontal lines on a page that may be applied during typesetting, drawn by hand, or printed on a negative.