Canon EOS Rebel T2i EOS REBEL T2i / EOS 550D Instruction Manual - Page 62

Z: Changing the ISO SpeedN Set the ISO speed (image sensor's sensitivity to light) to suit the ambient light level. In the Basic Zone modes, the ISO speed is set automatically (p.63). 1 Press the button. (9) X [ISO speed] will appear. ISO Speed Guide 2 Set the ISO speed. Turn the dial or press the key to select the ISO speed. You can also set the ISO speed in the viewfinder while turning the dial. With "AUTO" selected, the ISO speed will be set automatically (p.63). ISO Speed 100 - 400 400 - 1600 1600 - 6400, H Shooting Situation (No flash) Sunny outdoors Overcast skies or evening time Dark indoors or night Flash Range The higher the ISO speed, the farther the flash range will be (p.64). In the [7 Custom Functions (C.Fn)] menu, if [Highlight tone priority] is set to [1: Enable], the settable ISO speed range will be ISO 200 - 6400 (p.194). Using a high ISO speed or shooting in high-temperature conditions may result in more grainy images. Long exposures can also cause irregular colors in the image. When you shoot at high ISO speeds, noise (banding, dots of light, etc.) may appear. In the [7 Custom Functions (C.Fn)] menu, if [ISO expansion] is set to [1: On], "H" (equivalent to ISO 12800) can also be set (p.192). 62