Canon® EOS Rebel T1i/500D Digital Field Guide

Glossary

720p/1080i/1080p

High-definition video recording standards that refer to the vertical resolution, or the number of horizontal lines on the screen — either 720 or 1080 lines. Seven-hundred-twenty vertical lines translate to a width of 1280 pixels, and 1080 translates to 1920 pixels of horizontal resolution. The "p" stands for progressive scan, which displays the video frame all at once, and the "i" stands for interlaced, an analog compression scheme that allows 60 frames per second (fps) to be transmitted in the same bandwidth as 30 fps by displaying 50 percent of the video frame at a time.

A-DEP (Automatic depth of field)

The camera mode that automatically calculates sufficient depth of field for near and far subjects within the coverage of the seven AF focusing points, such as when several people are sitting at various distances from the camera.

AE

Automatic exposure.

AE Lock (Automatic Exposure Lock)

A camera control that lets the photographer lock the exposure from a meter reading. After the exposure is locked, the photographer can then recompose the image.

angle of view

The amount or area seen by a lens or viewfinder, measured in degrees. Shorter or wide-angle lenses and zoom settings have a greater angle of view. Longer or telephoto lenses and zoom settings have a narrower angle of view.

aperture

The lens opening through which light passes. Aperture size is adjusted by opening or closing the diaphragm. Aperture is expressed in f-numbers such as f/8, f/5.6, and so on. See also ...