Canon EOS Rebel XT - Manual (Page 55)

55
The ISO speed is a numeric indication of the sensitivity to light. A higher
ISO speed number indicates a higher sensitivity to light. Therefore, a
high ISO speed is suited for low light and moving subjects. However, the
image may look more grainy with noise, etc. On the other hand, a low
ISO speed is not suited for low light or action shots, but the image will
look finer. The camera can be set between ISO 100 and 1600 in 1-stop
increments.
The ISO speed is set automatically within ISO 100-400.
You can set the ISO speed to [100] [200] [400] [800] [1600].
1 Press the <
W W W WZ> button.
s The [ISO speed] menu will be
displayed.
2 Set the ISO speed.
¡ Press the <
V> key to select the
desired setting, then press <
0>.
Z Setting the ISO SpeedN
ISO Speed in the Basic Zone Modes
ISO Speed in the Creative Zone Modes
¡ At higher ISO speeds and higher ambient temperatures, the image will
look more grainy.
¡ High temperatures, high ISO speeds, or long exposures may cause
irregular colors in the image.