Using Your Nikon D5100 Monitor as a Viewfinder in Live View
Like most newer dSLR cameras, the Nikon D5100 offers Live View, a feature that enables you to use the monitor instead of the viewfinder to compose photos. Turning on Live View is also the first step in recording a movie; using the viewfinder isn't possible when you shoot movies.
In many respects, taking a picture in Live View mode is no different from regular, through-the-viewfinder photography. But a few critical steps, including focusing, work very differently when you switch on Live View.
The basics of taking advantage of Live View are pretty simple:
Switching to Live View: Rotate the Live View switch toward the back of the camera and release it. As soon as you take this step, you hear a clicking sound as the internal mirror that normally sends the image from the lens to the viewfinder flips up. The viewfinder goes dark, and the scene in front of the lens appears on the monitor.
Monitoring and adjusting camera settings: During Live View, critical settings appear superimposed atop the live preview instead of on the Shooting Information screen. You can still access the Quick Settings screen by pressing the Info Edit button and adjust other options via external buttons and menus as usual.
Shooting photos: Things work pretty much the same as for viewfinder photography — frame, focus, and press the shutter button. The main difference relates to autofocusing.
Recording movies: Press the red movie-record button to start and stop recording. Your focusing options are the same as for still photography in Live View mode.
Picture playback during Live View: Nothing different here, either: Just press the Playback button to shift from the Live View preview to playback mode. To return to shooting, press the button again or give the shutter button a quick half-press and release.
Exiting Live View mode: Rotate the Live View switch a second time.