A grayscale image printed with four colors of ink, usually black and three other colors for a total of four colors (called plates in the printing process).
radial blur
An interesting effect that blurs an image away from a center point or rotates it around a center point. The effect is similar to the photographic technique of making a zoom lens time exposure that creates a tunnel effect in toward the subject.
rasterize
The process of creating pixel data from vector elements. The conversion is often necessary before other Photoshop effects can be applied to a type layer.
red eye
An unwanted reflection from the subject's retina seen through the subject's iris. It's common with flash photography.
relief
The strength of a textured filter effect as it is applied to the image. In a burlap filter, for example, the relief affects the perceived depth of the weave.
render layer
See [rasterize]
resolution
The detail within a digital image, as determined by the number of pixels per inch.
RGB color model
A color process using red, green, and blue color variables. This is the native format for digital files, as created from scanners and digital cameras. There are multiple RGB color spaces to choose from, including Adobe, sRGB, and Apple RGB. Each offers a specific color range, and care should be taken when deciding which model to use.
rollover
A graphic that changes as you pass your mouse over a specific spot on the screen.
rotate
To change the presentation of an image, as if by placing a print of the image on the desktop and spinning itnothing about the image changes except the presentation.
