Adobe 29180155 User Guide - Page 304

299 Chapter 17: Glossary Photoshop Elements Glossary This glossary defines terms associated with digital imaging and photography, especially in relation to their use in Photoshop Elements Help. Glossary A acquisition module interface A plug-in that allows you to import photos from a digital camera or scanner. active layer The layer currently selected in the Layers palette. additive primaries Red, green, and blue. The human eye perceives all other colors as combinations of these three. To create colors besides the additive primaries, computer monitors combine these three colors of light. For instance, to create yellow, a monitor emits a combination of red and green light. When combined with each other at maximum intensity, the additive primaries create white. Compare subtractive primaries. adjustment layer A layer that lets you apply color and tonal adjustments to your image without permanently changing pixel values. Use adjustment layers to experiment with color and color tones. You can think of an adjustment layer as a veil through which the underlying layers are seen. ADM Adobe Dialog Manager. A file required for many plug-ins in Photoshop Elements. Adobe Color Engine Manages colors you view on-screen and in print. It is used to map the gamut of one color space to the gamut of another. Adobe Color Picker A built-in utility for specifying a foreground or background color in an Adobe application. Adobe RGB The RGB color space profile created by Adobe Systems, Incorporated. It provides a large gamut of colors. AGMLib An Adobe Graphics Manager library file, which Photoshop Elements installs with and requires. airbrush An brush option that lets you apply gradual tones to an image, simulating traditional airbrush techniques. Paint builds up as you apply more pressure. Using this option simulates the effect of spray-painting an image. aliasing The jagged edges seen at the edges of diagonal lines, arcs, and so on, caused by pixels lining up in a sawtooth pattern. alpha channels Masks, which let you manipulate, isolate, and protect specific parts of an image. In Photoshop Elements, alpha channels are called saved selections. To save an alpha channel, choose Select > Save Selection. To load an alpha channel, choose Select > Load Selection. ambient light The existing lighting conditions under which a photo is taken. animated GIF A series of images in GIF format that create the illusion of movement when they are displayed in sequence over time. anti-aliasing The smoothing of jagged edges in digital images by averaging the colors of the pixels at a boundary. arithmetic coded JPEG A type of file compression used to compress JPEG files.