Your Canon T8i/850D has so many features that it can be difficult to remember what each control does. To help you sort things out, this Cheat Sheet offers a handy reference to your camera's external controls and exposure modes. Print out this guide, tuck it in your camera bag, and get a head start on taking great photographs!
Controls on the Canon EOS Rebel T8i/850D Camera
If you’re not familiar with the T8i/850D camera, here’s a quick guide to its buttons, dials, and other external controls. The lens shown here is the 18–55mm kit lens; other lenses may have different features. See the next section of the Cheat Sheet for information about what the main buttons do.
Exposure Modes on the Canon EOS Rebel T8i/850D Camera
Your choice of exposure mode determines how much control you have over picture settings, including options that affect exposure, color, and autofocusing features. Set the exposure mode via the Mode dial shown here. For the most control, switch to P, Tv, Av, or M mode. Canon refers to those modes as Creative Zone modes; the others are Basic Zone modes.
| Exposure Mode | Description |
| Scene Intelligent Auto | Completely automatic photography; the camera analyzes the scene and tries to choose settings that produce the best results. |
| SCN (Scene) | Automatic modes for capturing specific types of scenes, including portraits, landscapes, and nighttime shots. |
| Creative Filter | Enables you to add special effects to pictures and movies as you shoot them. |
| P (Programmed Autoexposure) | The camera selects both the f-stop and shutter speed to ensure proper exposure, but you can choose from multiple combinations of the two settings. |
| Tv (Shutter-priority Autoexposure) | You set shutter speed, and the camera selects the f-stop that will produce a good exposure. |
| Av (Aperture-priority Autoexposure) | You select f-stop, and the camera selects the shutter speed that will produce a good exposure. |
| M (Manual Exposure) | You control both the shutter speed and f-stop. |
Functions of Buttons and Other Controls on the Canon EOS T8i/850D
It’s great to have a map to the buttons and controls on your camera, but it’s not a lot of help if you can’t remember which button to press when (and why). So, here’s a quick recap of what you can do with each button. Note: This information concentrates on features available when you shoot in the P, Tv, Av, and M exposure modes. A few features also work in other modes.
| This Control | . . . Performs These functions |
| Mode dial | Sets the exposure mode, which determines how much control you have over picture settings. For the most control, choose P, Tv, Av, or M. |
| Menu button | Press to display and hide camera menus; rotate the Main dial to cycle through menu pages. |
| Info button | During playback, Live View photography, and Movie shooting, changes the data display. During viewfinder photography, toggles between the normal information display and an electronic level. |
| Live View/Movie record button | Press to toggle Live View on and off. When the camera is in Movie mode, press to start and stop recording. |
| AF ON button | When pressed, performs the same function as pressing the shutter button halfway, initiating autofocusing and autoexposure. |
| Q button | Activates Quick Control mode, which provides fast access to shooting and playback settings. |
| Quick Control dial and Set button | The dial has an outer ring that you rotate to scroll through menus, settings, and other options. You also can press the left, right, top, and bottom edge of the dial to choose certain settings. In most cases, you press the Set button at the center of the dial to lock in your choice of setting. During viewfinder shooting, press the dial’s edges to access the following settings: top edge, White Balance; right edge, AF Operation; bottom edge, Picture Style; left edge, Drive mode. |
| AF Area Selection button | Press to display the AF Area Selection setting, which controls which autofocus point or zones the camera uses to set focusing distance. |
| ISO button | Press to display a screen where you can adjust the ISO setting, which determines how sensitive the camera is to light. |
| DISP button | During viewfinder photography, enables you to manually turn the monitor on and off. |
| AE Lock/FE Lock/Index/Reduce button | During shooting, press to lock autoexposure (AE) or to lock flash exposure (FE). During playback, press to cycle from single-image view to index (thumbnails) view. If the displayed image or live preview is magnified, press to reduce the magnification level. |
| AF Point Selection/Magnify button | During viewfinder photography, press to display the AF Area Selection screen. (You still must use the AF Area Selection button to change the setting.) In Playback mode, press to magnify the image on the monitor. In Live View or Movie mode, you also can magnify the display under certain circumstances. |
| Erase/Lock button | While reviewing pictures, press to erase currently displayed or selected photos. When the camera is in shooting mode, pressing the button locks the Quick Control dial so that rotating the dial has no effect. Press the button again to restore the dial’s function. You can also use the button to lock and unlock the touchscreen and Main dial; set your preferences through the Multi Function Lock option, found on Setup Menu 4. |
| Playback button | Toggles picture playback on and off. |
| Depth-of-Field Preview button | Press to temporarily set the aperture to the selected f-stop so that you can see an approximation of depth of field in the viewfinder. |
| Lens-release button | Press to disengage the lens from the camera’s lens mount so that you can remove the lens. |
