Top of The Camera

Controls on the top of the camera, show in Figure 1.5, enable you to use your thumb and index finger on your right hant to control common adjustments quickly. Here is a look at the top of the camera.

• Focal plane mark. This is the point from which the lens's minimum, or closest, focusing distance is measured.
• Hot shoe. You can mount an accessory Speedlite or third-party flash unit here. The contacts provide communication between the flash and the T3i/600D.
• Mode dial. Turning this dial changes the shooting mode. Just line up the shooting mode you want to use the white mark beside the dial. Shooting modes are detailed.
• Power switch. This button switches the camera on and off.
• ISO speed button. Pressing this button display the ISO speed screen on the LCD so that you can change the ISO setting, which determines the sensor's sensitivity to light. In P, Tv, Av, M, and A-DEP shooting modes, you can select Auto ISO to have the camera automatically determine the ISO from 100 to 6400, or you can set the ISO yourself. Alternately, you can set the highest ISO setting that the Auto ISO option users. You can also turn on on a additional high ISO setting, equivalent to 12800, by setting Custom Fuction 1-2. In all automatically shooting modes, such as Portrait and Landscape, the camera automatically sets the ISO between 100 and 3200.
• DISP. button. Press this button to turn the LCD on and off, although you can change is behavior on the Setup 2 menu. In Movie mode, holding the DISP. button and pressing the zoom in or zoom out buttons enables you to use digital zoom at a 3X to 10X zoom.
• Main dial. Described early in this chapter.
• Shutter button. Described in the previous section.