Mode dial

A mode dial or camera dial is a dial used on digital cameras to change the camera's mode. Most digital cameras, especially dSLR and SLR-like cameras, employ a mode dial. On point-and-shoot cameras which employ these dials, the mode dials generally offer a range of scene types. On dSLR cameras and SLR-like cameras, mode dials usually offer access to manual settings. Many point-and-shoot cameras are compact and don't have mode dials; these cameras have all settings accessed through internal menus. On some SLR lenses, the lenses themselves offer control over things such as aperture, reducing the need for the mode dial.
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