Lens mount Nikon F mount (with AF contacts)
Effective angle of view Approx. 1.5 x lens focal length (Nikon DX format)
Effective pixels
Effective pixels 14.2 million
Image sensor
Image sensor 23.1 x 15.4 mm CMOS sensor
Total pixels 14.8 million
Dust-reduction system Image sensor cleaning, Airflow Control System, Image Dust Off reference data (optional Capture NX 2 software required)
Storage
Image size (pixels) " 4,608 x 3,072 [L] " 3,456 x 2,304 [M] " 2,304 x 1,536 [S]
File format " NEF (RAW)
" JPEG: JPEG-Baseline compliant with fine (approx. 1:4), normal (approx. 1:8), or basic (approx. 1:16) compression
" NEF (RAW) + JPEG: Single photograph recorded in both NEF (RAW) and JPEG formats
![](http://www.lavishavenue.com/wp-content/uploads/2010/08/nikon-d3100.jpg)
Media SD (Secure Digital), SDHC and SDXC memory cards
File system DCF (Design Rule for Camera File System) 2.0, DPOF (Digital Print Order Format), Exif 2.21
![](http://ecx.images-amazon.com/images/I/51BzdqJjdVL._SL500_AA400_.jpg)
Frame coverage Approx. 95% horizontal and 95% vertical
Magnification Approx. 0.8 x (50 mm f/1.4 lens at infinity, -1.0 m-1)
Eyepoint 18 mm (-1.0 m-1)
Diopter adjustment -1.7 to +0.5 m-1
Focusing screen Type B BriteView Clear Matte Mark VII screen
Reflex mirror Quick return
Lens aperture Instant return, electronically
![](http://ecx.images-amazon.com/images/I/51XD339z%2B-L.jpg)
" Type G or D AF NIKKOR without built-in autofocus motor: All functions except autofocus supported. IX NIKKOR lenses not supported.
" Other AF NIKKOR: All functions supported except autofocus and 3D color matrix metering II. Lenses for F3AF not supported.
" Type D PC NIKKOR: All functions supported except autofocus and some shooting modes.
" AI-P NIKKOR: All functions supported except autofocus and 3D color matrix metering II.
" Non-CPU: Autofocus not supported. Can be used in exposure mode M, but exposure meter does not function.
Note: Electronic rangefinder can be used if lens has a maximum aperture of f/5.6 or faster.
Shutter
Type Electronically controlled vertical-travel focal-plane shutter
Speed 1/4000 to 30 s in steps of 1/3 EV, Bulb
Flash sync speed X=1/200 s; synchronizes with shutter at 1/200 s or slower
Release
Release mode (single frame),(continuous),(self-timer),(quiet shutter release)
Frame advance rate Up to 3 fps (manual focus, mode M or S, shutter speed 1/250 s or faster, and other settings at default values)
Self-timer 2 s, 10 s
Exposure
Metering TTL exposure metering using 420-pixel RGB sensor
Metering method " Matrix: 3D color matrix metering II (type G and D lenses); color matrix metering II (other CPU lenses)
" Center-weighted: Weight of 75% given to 8-mm circle in center of frame
" Spot: Meters 3.5-mm circle (about 2.5% of frame) centered on selected focus point
Range
(ISO 100, f/1.4 lens, 20°C/68°F) " Matrix or center-weighted metering: 0 to 20 EV
" Spot metering: 2 to 20 EV
Exposure meter coupling CPU
Exposure modes Auto modes (auto, auto [flash off]); scene modes (portrait; landscape; child; sports; close up; night portrait);
programmed auto with flexible program (P); shutter-priority auto (S); aperture-priority auto (A); manual (M)
Exposure compensation -5 to +5 EV in increments of 1/3 EV
Exposure lock Luminosity locked at detected value with AE-L/AF-L button
ISO sensitivity
(Recommended Exposure Index) ISO 100 to 3200 in steps of 1 EV; can also be set to approx. 1 EV above ISO 3200 (ISO 6400 equivalent) or to
approx. 2 EV above ISO 3200 (ISO 12800 equivalent); auto ISO sensitivity control available
Active D-Lighting On, Off
Focus
Autofocus Nikon Multi-CAM 1000 autofocus sensor module with TTL phase detection, 11 focus points (including one
cross-type sensor), and AF-assist illuminator (range approx. 0.5 to 3m/1 ft. 8 in. to 9 ft. 10 in.)
Detection range -1 to +19 EV (ISO 100, 20°C/68°F)
Lens servo " Autofocus (AF): Single-servo AF (AF-S); continuous-servo AF (AF-C); auto AF-S/AF-C selection (AF-A); predictive focus tracking activated automatically according to subject status
" Manual focus (MF): Electronic rangefinder can be used
Focus point Can be selected from 11 focus points
AF-area mode Single-point AF, dynamic-area AF, auto-area AF, 3D-tracking (11 points)
Focus lock Focus can be locked by pressing shutter-release button halfway (single-servo AF) or by pressing AE-L/AF-L button
Flash
Built-in flash Auto, Portrait, Child, Close up, Night portrait: Auto flash with auto pop-up
P, S, A, M: Manual pop-up with button release
Guide number Approx. 12/39, 13/43 with manual flash (m/ft, ISO 100, 20°C/68°F)
Flash control " TTL: i-TTL balanced fill-flash and standard i-TTL flash for digital SLR using 420-pixel RGB sensor are available with built-in flash and SB-900, SB-800, SB-600, or SB-400 (i-TTL balanced fill-flash is available when matrixor center-weighted metering is selected)
" Auto aperture: Available with SB-900/SB-800 and CPU lens
" Non-TTL auto: Supported flash units include SB-900, SB-800, SB-80DX, SB-28DX, SB-28, SB-27, and SB-22S
" Distance-priority manual: Available with SB-900 and SB-800
Flash mode Auto, auto with red-eye reduction, fill-flash, auto slow sync, auto slow sync with red-eye correction, and rear curtain with slow sync
Flash compensation -3 to +1 EV in increments of 1/3 EV
Flash-ready indicator Lights when built-in flash or optional flash unit such as SB-900, SB-800, SB-600, or SB-400 is