The D5100's live view implementation is very similar to the D3100's, and as such, most of the commentary on this page applies equally to both cameras. The D5100 live view mode is initiated using the physical lever positioned around the base of the exposure mode dial, as opposed to the same switch on the D3100, which sits on the thumbgrip on the rear of the camera.
While the D3100's live view lever is well-placed for operation by your thumb, the D5100's is slightly more awkward. To activate live view, it is necessary to take the camera away from your eye and shift your grip on the camera. On the plus side, this does mean that it is hard to accidentally enter live view mode (and why would you want to activate it with your eye to the viewfinder anyway?) As well as being a gateway to movie shooting (more on that later) live view also gives you access to two 'missing' features, in the shape of depth of field preview and mirror lock up.
In the PAS shooting modes, the live view image will darken or brighten to reflect any exposure compensation you set, although sadly there's no live histogram to help judge the optimum exposure. In M mode, though, the display makes no attempt to reflect the currently-set exposure level at all. To compound this there's no exposure meter display, so you have to switch to the control panel by a press of the 'i' button to check your exposure (temporarily exiting the live view display in the process).
Magnification of the Live View display is available in 5 steps, and unlike the D3100, the magnified image is crisp and clear, which makes precise manual focus a very straightforward affair. One genuinely useful characteristic is that, like the D7000, the D5100 holds the mirror up all the time in live view mode, and doesn't have to drop it down to reset the shutter and make the exposure. As a result, you can use live view as a proxy for mirror lockup to minimize vibration when shooting off a tripod, in concert with either the remote release or the self timer. Simply enter live view to flip the mirror up, then release the shutter a couple of seconds later when any vibrations have died away.
|Movie showing mirror behaviour during live view shooting. The mirror does not flip down during shooting.|
The D5100's Live View aperture control behavior also shows an odd quirk that first appeared way back on the D300. When you enter Live View, the camera will stop down to the currently set or metered value (offering an undocumented depth-of-field preview in the process), but what it won't then do is readjust the diaphragm 'live' if you change the aperture setting. It will honour the set aperture when actually making an exposure, and indeed return to live view at that aperture afterwards; alternatively you can force it to readjust by exiting and re-entering live view.
This behavior is, simply, a bug (albeit a long-standing one) rather than some fundamental limitation of the F-mount; the D3 series bodies can continuously adjust aperture in live view, exactly as you'd expect. And it does have a couple of practical consequences - it can give a misleading impression of the depth of field you'll end up getting, and it further complicates manual focus as you have to remember to always initiate live view at an appropriate aperture (normally with the lens wide open). Also, in lower light conditions the display can appear dark and/or grainy if you enter live view with the camera set to a small aperture. As we'll see later, this bug has a curious knock-on effect when shooting movies too.
Overall, the D5100's Live View is certainly quite functional as a basic means of framing for stills and video shooting, and to its credit has unusually good autofocus for an SLR. However it lacks many of the more advanced features you'll find on more expensive SLRs, or full-time live view cameras such as the Sony NEXs or Olympus PENs.
The D5100 offers Full HD (1080p) movie recording. Unlike most other SLRs at this price level, the basic video controls are integrated neatly into the overall design - movies can be shot in any exposure mode simply by engaging live view and pressing the dedicated record button (there's no need to set the camera to a specific movie mode first).
The D5100 gives a choice of three video resolutions - 1920 x 1080 Full HD, 1280 x 720 HD, and 640 x 424 SD - which all use progressive (i.e. non-interlaced) frame recording. Files are encoded in the .MOV Quicktime format using the currently-standard H.264 compression. Nikon's choice of the .MOV format makes the files sharing-friendly for playback on computers or uploading to the web, but does mean they can't be recorded directly to DVD without conversion (unlike AVCHD).
The built-in internal microphone captures mono audio only, but there is the option of connecting an external, stereo unit. Microphone sensitivity is adjustable in 3 stages (plus auto and 'off') but there is no wind-cut option. Some basic video editing options are available in-camera via the retouch menu, allowing you to trim clips to selected start/end points, or extract individual frames as still images.
|Sizes|| 1920x1080p: 30, 25 or 24 fps
1280x720p (HD): 30, 25 or 24 fps
640x480 (SD): 24fps
|Audio recording||Built-in mono mic, with external mic option. Linear PCM encoding|
|Max file size per clip||4GB|
|Max running time per clip||Approx 10 min|
Using Movie Mode
Movie shooting is relatively well-integrated into the D5100's control system: simply engage live view using the large lever on the top, then press the red button to the left of the shutter release to start recording. At this point the live view image will crop down to the 16:9 aspect ratio if you're recording HD footage. You can record a still image while shooting a movie simply by pressing the shutter button - however this does also stop movie recording.
Shutter speed, aperture and ISO are usually set automatically, and you can press the AEL button during recording to lock the exposure. In the PAS modes you can apply exposure compensation up to +/-3 EV, either before or during filming. In A and M you can also control the aperture the camera uses for filming - although due to the bug described in our Live View section, not in the way you might think (or indeed the manual suggests).
The crucial point to remember is that the camera enters live view at the currently set (or metered) aperture, but then remains there no matter what changes you make, until you either exit live view or take a picture. This means, bizarrely, that movies aren't always recorded at the currently-set aperture. For example, if in A mode you set the camera to F5.6 and enter live view, then change the aperture to F16 and start recording, your movie will be shot at F5.6. But if you then take a still image and restart movie recording, your new clip will now be shot at F16. This is, obviously, somewhat confusing until you understand what's going on - at which point it's merely inexplicable.
The D5100's fully articulated screen is a real boon for shooting movies, but like all DSLRs, it is primarily designed for shooting stills. Despite it's flexible screen, the D5100 still forces you to shoot hand-held footage with the camera held out in front of you so you can see the image on the LCD, which isn't a particularly comfortable or stable way of working. In our opinion the stills cameras that work best for shooting video are those like the Panasonic DMC-G2 and GH2, and the Sony Alpha SLT-A33/55, which feature electronic viewfinders.
Movie mode displays
|There is a choice of movie sizes and frame rates available. The full HD 1080p mode is only available at the supposedly 'cinematic' 24 fps.||The sensitivity of the built-in stereo microphone can be set to auto, or manually set to one of three levels. It can also be turned off if desired.|
Video quality comments
Our comments about the D5100's image quality in video mode precisely match those that we made about the D3100, and indeed the higher end D7000. On the whole the D5100's movies are look great, with smooth motion and impressively low noise in dim light. The sound quality from the built-in microphone is quite acceptable for casual shooting, but nothing to write home about. In quiet situations, though, it will easily pick up noises from camera operations - zooming, or autofocus in AF-F mode, so you may wish to turn sound recording off in such cases.
Like all DSLRs the D5100 can suffer from 'jello' effects when panning or recording subjects that are moving fast across the frame, with vertical lines tilting to diagonals due to the use of a 'rolling' shutter. However you have to pan pretty fast to really see it, and it's not at all likely to be a serious problem in normal use. We shot a lot of video with the D5100, and only noticed the effect in a handful of non-typical scenes (such as when the camera was pointed out of a biplane, during a bumpy flight).
Predictably enough the internal microphone will tend to record the sound of the lens focusing and, though it can be drowned-out by the sound you were actually hoping to record, serious filmmakers will find themselves needing an external microphone.
Just like the D3100, the D5100's AF-F continuous focusing mode has to count as a qualified success - in the samples below you can see it twitching in and out of focus, and occasionally failing to establish the correct focus for a second or two on what is a relatively undemanding subject. Obviously it's better then not being able to refocus at all, but it can't match its mirrorless competitors such as the Sony NEXs or Panasonic G series, substantially because these have lenses specifically designed for the job.
These videos were shot in a range of different environments, and at a range of different settings. We are pleased to announce that dpreview.com is now partnering with Vimeo to bring you high-quality embedded video in our test pages, but as always, the original files are available for download from the links beneath the thumbnails. We've turned HD playback on by default for our embedded videos, but depending on the speed of your internet connection, you may get better performance by turning it off.
Sample video 1
This shot was taken handheld, at the long end of the new Tamron SP 70-300mm f/4-5.6 Di Vc lens. Sound reproduction from the built-in microphone is impressively faithful, and AF-F does a good job of tracking the aircraft until almost the end of its takeoff run, at which point the video goes dramatically out of focus, but is brought back with a half-press of the shutter button.
|1920 x 1080 30 fps, MPEG-4 .MOV file, 13 sec. 33 MB Click here to download original .MOV file|
Sample video 2
This video was shot from the car of a roller coaster, and demonstrates the limitations of the D5100's built-in microphone. Wind 'boom' is a major feature of this short clip, and the voices of the passengers in the car (sat behind the camera) have rather too much prominence on the soundtrack, as well. From an image quality point of view though, the footage is smooth, colorful and detailed.
|1920 x 1080 30 fps, MPEG-4 .MOV file, 18 sec. 45.4 MB Click here to download original .MOV file|
Sample video 3Shot on the same bright day as the previous clip, this footage again demonstrates the D5100's ability to capture crisp, smooth video of rapidly moving subjects. Also like the previous clip, conversations happening behind the camera are prominent on the soundtrack, which gives the sound an unfocussed, 'booming' aspect. An external microphone would have solved this problem.
|1920 x 1080 30 fps, MPEG-4 .MOV file, 9 sec. 22.3 MB Click here to download original .MOV file|
Sample video 4This video was shot in aperture priority mode at f/25 for maximum depth of field and as low a shutter speed as possible (30sec). The slow shutter speed was desirable because I wanted to blur the motion of the aircraft's propellers, which gives a much more attractive result than the slow-moving, banana-shaped propeller blades that characterise video shot at too fast a shutter speed.
|1920 x 1080 30 fps, MPEG-4 .MOV file, 14 sec. 36 MB Click here to download original .MOV file|
Sample video 5This simple zoom shot demonstrates the propensity of the D5100's built-in microphone to pick wind sound. In this clip, shot in a moderate breeze, the kit 18-55mm zoom is zoomed slowly from 55mm to 18mm, handheld (with VR turned on).
|1920 x 1080 30 fps, MPEG-4 .MOV file, 12 sec. 32.1 MB Click here to download original .MOV file|
Sample video 6This movie clip was shot in bright, side-lit conditions, in aperture priority mode. Aperture was set to f/10 for wide depth of field, and focus was set manually. This video demonstrates again, how well the D5100 copes with capturing fast moving subjects, and also shows that you don't necessarily need to engage AF to do so (sometimes, all you need to do is to ensure a reasonably wide depth of field).
|1920 x 1080 30 fps, MPEG-4 .MOV file, 8 sec. 21.15 MB Click here to download original .MOV file|