Canon EOS 40D - Manual (Page 59)

59
Set the ISO speed (image sensor’s sensitivity to light) to suit the
ambient light level. For example, when you increase the ISO speed
(higher number) for low light, a faster shutter speed can be used and
camera shake will be less prone to occur. The effective range of the
flash will also increase.
The ISO speed is set automatically within ISO 100 - 800.
ISO 100 - 1600 can be set in 1/3-stop increments. Also, the “Auto”
setting will change the ISO speed automatically to suit the ambient light
level.
1
Press the <m> button. (9)
X The current ISO speed will be
displayed on the LCD panel.
In the Basic Zone modes, “Auto” will
be displayed on the LCD panel.
2
Set the ISO speed.
While looking at the LCD panel or
viewfinder, turn the <6> dial.
With “Auto”, the ISO speed will be set
automatically.
i : Setting the ISO SpeedN
ISO Speed in the Basic Zone Modes
ISO Speed in the Creative Zone Modes
Using a high ISO speed or shooting in high-temperature conditions may
result in more grainy images.
High temperatures, high ISO speeds, or long exposures may cause
irregular colors in the image.
With [8C.Fn I -3] (ISO expansion) set to [1: On] (p.154), “H” (ISO 3200)
can also be set.