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Nikon D7000 vs D3100

The Nikon D7000 and the Nikon D3100 are two digital cameras that were revealed to the public, respectively, in September 2010 and August 2010. Both are DSLR (Digital Single Lens Reflex) cameras that are equipped with an APS-C sensor. The D7000 has a resolution of 16.1 megapixels, whereas the D3100 provides 14.2 MP.

Below is an overview of the main specs of the two cameras as a starting point for the comparison.

Headline Specifications
Nikon D7000
versus
Nikon D3100
Nikon D7000   Nikon D3100
Digital single lens reflex Digital single lens reflex
Nikon F mount lenses Nikon F mount lenses
16.1 MP – APS-C sensor 14.2 MP – APS-C sensor
1080/24p Video 1080/24p Video
ISO 100-6,400 (100 - 25,600) ISO 100-3,200 (100 - 12,800)
Optical viewfinder Optical viewfinder
3.0" LCD – 921k dots 3.0" LCD – 230k dots
Fixed screen (not touch-sensitive) Fixed screen (not touch-sensitive)
6 shutter flaps per second 3 shutter flaps per second
Weathersealed bodynot weather sealed
1050 shots per battery charge550 shots per battery charge
132 x 105 x 77 mm, 780 g 124 x 96 x 75 mm, 505 g
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Going beyond this snapshot of core features and characteristics, what are the differences between the Nikon D7000 and the Nikon D3100? Which one should you buy? Read on to find out how these two cameras compare with respect to their body size, their imaging sensors, their shooting features, their input-output connections, and their reception by expert reviewers.

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Body comparison

An illustration of the physical size and weight of the Nikon D7000 and the Nikon D3100 is provided in the side-by-side display below. The two cameras are presented according to their relative size. Three consecutive perspectives from the front, the top, and the back are available. All size dimensions are rounded to the nearest millimeter.

The D3100 can be obtained in two different colors (black, red), while the D7000 is only available in black.

Size Nikon D7000 vs Nikon D3100
Compare D7000 versus D3100 top
Comparison D7000 or D3100 rear

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Nikon D3100 is notably smaller (14 percent) than the Nikon D7000. Moreover, the D3100 is substantially lighter (35 percent) than the D7000. It is worth mentioning in this context that the D7000 is splash and dust resistant, while the D3100 does not feature any corresponding weather-sealing.

The above size and weight comparisons are to some extent incomplete since they do not consider the interchangeable lenses that both of these cameras require. In this particular case, both cameras feature the same lens mount, so that they can use the same lenses. You can compare the optics available in the Nikon Lens Catalog.

Concerning battery life, the D7000 gets 1050 shots out of its Nikon EN-EL15 battery, while the D3100 can take 550 images on a single charge of its Nikon EN-EL14 power pack.

The table below summarizes the key physical specs of the two cameras alongside a broader set of comparators. In case you want to display and compare another camera duo, you can use the CAM-parator app to select your camera combination among a large number of options.

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Body Specifications
# image Camera
Model
Camera
Width
Camera
Height
Camera
Depth
Camera
Weight
Battery
Life
Weather
Sealing
Camera
Launch
Launch
Price (USD)
Street
Price
1.
 
Nikon D7000 132 mm 105 mm 77 mm 780 g 1050 Y Sep 2010 1,499ebay.com
2.
 
Nikon D3100 124 mm 96 mm 75 mm 505 g 550 n Aug 2010 599ebay.com
3.
 
Canon 60D 145 mm 106 mm 79 mm 755 g 1100 Y Aug 2010 1,399ebay.com
4.
 
Canon 7D 148 mm 111 mm 74 mm 860 g 800 Y Sep 2009 1,699ebay.com
5.
 
Nikon D7500 136 mm 104 mm 73 mm 720 g 950 Y Apr 2017 1,299 amazon.com
6.
 
Nikon D7100 136 mm 107 mm 76 mm 765 g 950 Y Feb 2013 1,199ebay.com
7.
 
Nikon D3200 125 mm 96 mm 77 mm 505 g 540 n Apr 2012 599ebay.com
8.
 
Nikon D5100 128 mm 97 mm 79 mm 560 g 660 n Apr 2011 749ebay.com
9.
 
Nikon D300S 147 mm 115 mm 81 mm 938 g 950 Y Jul 2009 1,799ebay.com
10.
 
Nikon D3000 126 mm 97 mm 64 mm 536 g 500 n Jul 2009 599ebay.com
11.
 
Nikon D5000 127 mm 104 mm 80 mm 590 g 510 n Apr 2009 749ebay.com
12.
 
Nikon D90 132 mm 103 mm 77 mm 703 g 850 n Aug 2008 1,299ebay.com
13.
 
Nikon D300 147 mm 114 mm 74 mm 925 g 1000 Y Aug 2007 1,799ebay.com
14.
 
Nikon D200 147 mm 113 mm 74 mm 920 g 400 Y Nov 2005 1,699ebay.com
Note: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.
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Any camera decision will obviously take relative prices into account. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The D3100 was launched at a markedly lower price (by 60 percent) than the D7000, which puts it into a different market segment. Usually, retail prices stay at first close to the launch price, but after several months, discounts become available. Later in the product cycle and, in particular, when the replacement model is about to appear, further discounting and stock clearance sales often push the camera price considerably down. Then, after the new model is out, very good deals can frequently be found on the pre-owned market.

Sensor comparison

The imaging sensor is at the core of digital cameras and its size is one of the main determining factors of image quality. A large sensor will tend to have larger individual pixels that provide better low-light sensitivity, wider dynamic range, and richer color-depth than smaller pixel-units in a sensor of the same technological generation. Furthermore, a large sensor camera will give the photographer more possibilities to use shallow depth-of-field in order to isolate a subject from the background. On the downside, larger sensors tend to be more expensive and lead to bigger and heavier cameras and lenses.

Both cameras under consideration feature an APS-C sensor, but their sensors differ slightly in size. The sensor area in the D3100 is 4 percent smaller. They nevertheless have the same format factor of 1.5. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.

Nikon D7000 and Nikon D3100 sensor measures

With 16.1MP, the D7000 offers a higher resolution than the D3100 (14.2MP), but the D7000 has smaller individual pixels (pixel pitch of 4.80μm versus 5.01μm for the D3100). It is noteworthy in this context that the two cameras were released in close succession, so that their sensors are from the same technological generation.

The resolution advantage of the Nikon D7000 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the D7000 for good quality output (200 dots per inch) amounts to 24.6 x 16.3 inches or 62.6 x 41.5 cm, for very good quality (250 dpi) 19.7 x 13.1 inches or 50.1 x 33.2 cm, and for excellent quality (300 dpi) 16.4 x 10.9 inches or 41.7 x 27.6 cm. The corresponding values for the Nikon D3100 are 23 x 15.4 inches or 58.5 x 39 cm for good quality, 18.4 x 12.3 inches or 46.8 x 31.2 cm for very good quality, and 15.4 x 10.2 inches or 39 x 26 cm for excellent quality prints.

The Nikon D7000 has a native sensitivity range from ISO 100 to ISO 6400, which can be extended to ISO 100-25600. The corresponding ISO settings for the Nikon D3100 are ISO 100 to ISO 3200, with the possibility to increase the ISO range to 100-12800.

Technology-wise, both cameras are equipped with CMOS (Complementary Metal–Oxide–Semiconductor) sensors. Both cameras use a Bayer filter for capturing RGB colors on a square grid of photosensors. This arrangement is found in most digital cameras.

D7000 versus D3100 MP

Since 2007, DXO Mark has published sensor performance measurements that have been derived using a consistent methodology. This service assesses and scores the color depth ("DXO Portrait"), dynamic range ("DXO Landscape"), and low-light sensitivity ("DXO Sports") of camera sensors, and also publishes an overall camera score. Of the two cameras under review, the D7000 provides substantially higher image quality than the D3100, with an overall score that is 13 points higher. This advantage is based on 1 bits higher color depth, 2.6 EV in additional dynamic range, and 0.3 stops in additional low light sensitivity. The adjacent table reports on the physical sensor characteristics and the outcomes of the DXO sensor quality tests for a sample of comparator-cameras.

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Sensor Characteristics
# image Camera
Model
Sensor
Class
Resolution
(MP)
Horiz.
Pixels
Vert.
Pixels
Video
Format
DXO
Portrait
DXO
Landscape
DXO
Sports
DXO
Overall
1.
 
Nikon D7000 APS-C 16.1 4928 32641080/24p23.513.9116780
2.
 
Nikon D3100 APS-C 14.2 4608 30721080/24p22.511.391967
3.
 
Canon 60D APS-C 17.9 5184 34561080/30p22.211.581366
4.
 
Canon 7D APS-C 17.9 5184 34561080/30p22.011.785466
5.
 
Nikon D7500 APS-C 20.7 5568 37124K/30p24.314.0148386
6.
 
Nikon D7100 APS-C 24.0 6000 40001080/60p24.213.7125683
7.
 
Nikon D3200 APS-C 24.1 6016 40001080/30p24.113.2113181
8.
 
Nikon D5100 APS-C 16.1 4928 32641080/30p23.513.6118380
9.
 
Nikon D300S APS-C 12.2 4288 2848720/24p22.512.278770
10.
 
Nikon D3000 APS-C 10.0 3872 2592none22.311.156362
11.
 
Nikon D5000 APS-C 12.2 4288 2848720/24p22.712.586872
12.
 
Nikon D90 APS-C 12.2 4288 2848720/24p22.712.597773
13.
 
Nikon D300 APS-C 12.2 4288 2848none22.112.067967
14.
 
Nikon D200 APS-C 10.0 3872 2592none22.311.558364
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Many modern cameras are not only capable of taking still images, but can also record movies. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, and both provide the same movie specifications (1080/24p).

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Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. The D7000 and the D3100 are similar in the sense that both have an optical viewfinder. The latter is useful for getting a clear image for framing even in brightly lit environments. The viewfinder in the D7000 offers a wider field of view (100%) than the one in the D3100 (95%), so that a larger proportion of the captured image is visible in the finder. In addition, the viewfinder of the D7000 has a higher magnification (0.63x vs 0.53x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The table below summarizes some of the other core capabilities of the Nikon D7000 and Nikon D3100 in connection with corresponding information for a sample of similar cameras.

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Core Features
# image Camera
Model
Viewfinder
(Type or
000 dots)
Control
Panel
(yes/no)
LCD
Specifications
(inch/000 dots)
LCD
Attach-
ment
Touch
Screen
(yes/no)
Max
Shutter
Speed *
Max
Shutter
Flaps *
Built-in
Flash
(yes/no)
Built-in
Image
Stab
1.
 
Nikon D7000optical Y3.0 / 921 fixed n 1/8000s 6.0/s Y n
2.
 
Nikon D3100optical n3.0 / 230 fixed n 1/4000s 3.0/s Y n
3.
 
Canon 60Doptical Y3.0 / 1040 swivel n 1/8000s 5.3/s Y n
4.
 
Canon 7Doptical Y3.0 / 920 fixed n 1/8000s 8.0/s Y n
5.
 
Nikon D7500optical Y3.2 / 922 tilting Y 1/8000s 8.0/s Y n
6.
 
Nikon D7100optical Y3.2 / 1229 fixed n 1/8000s 6.0/s Y n
7.
 
Nikon D3200optical n3.0 / 921 fixed n 1/4000s 4.0/s Y n
8.
 
Nikon D5100optical n3.0 / 921 swivel n 1/4000s 4.0/s Y n
9.
 
Nikon D300Soptical Y3.0 / 920 fixed n 1/8000s 7.0/s Y n
10.
 
Nikon D3000optical n3.0 / 230 fixed n 1/4000s 3.0/s Y n
11.
 
Nikon D5000optical n2.7 / 230 full-flex n 1/4000s 4.0/s Y n
12.
 
Nikon D90optical Y3.0 / 920 fixed n 1/4000s 4.5/s Y n
13.
 
Nikon D300optical Y3.0 / 922 fixed n 1/8000s 6.0/s Y n
14.
 
Nikon D200optical Y2.5 / 230 fixed n 1/8000s 5.0/s Y n
Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one.
padding

One feature that is present on the D7000, but is missing on the D3100 is a top-level LCD. While being, of course, smaller than the rear screen, the control panel conveys some of the essential shooting information and can be convenient for quick and easy settings verification.

The Nikon D7000 has an intervalometer built-in. This enables the photographer to capture time lapse sequences, such as flower blooming, a sunset or moon rise, without purchasing an external camera trigger and related software.

Concerning the storage of imaging data, both the D7000 and the D3100 write their files to SDXC cards. The D7000 features dual card slots, which can be very useful in case a memory card fails. In contrast, the D3100 only has one slot.

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Connectivity comparison

For some imaging applications, the extent to which a camera can communicate with its environment can be an important aspect in the camera decision process. The table below provides an overview of the connectivity of the Nikon D7000 and Nikon D3100 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

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Input-Output Connections
# image Camera
Model
Hotshoe
Port
Internal
Mic / Speaker
Microphone
Port
Headphone
Port
HDMI
Port
USB
Port
WiFi
Support
NFC
Support
Bluetooth
Support
1.
 
Nikon D7000Ymono / monoY-mini2.0---
2.
 
Nikon D3100Ymono / mono--mini2.0---
3.
 
Canon 60DYmono / monoY-mini2.0---
4.
 
Canon 7DYmono / -Y-mini2.0---
5.
 
Nikon D7500Ystereo / monoYYmini2.0Y-Y
6.
 
Nikon D7100Ystereo / monoYYmini2.0---
7.
 
Nikon D3200Ymono / monoY-mini2.0---
8.
 
Nikon D5100Ymono / monoY-mini2.0---
9.
 
Nikon D300SYstereo / monoY-mini2.0---
10.
 
Nikon D3000Y- / ----2.0---
11.
 
Nikon D5000Ymono / mono--mini2.0---
12.
 
Nikon D90Ymono / mono--mini2.0---
13.
 
Nikon D300Y- / ---mini2.0---
14.
 
Nikon D200Y- / ----2.0---
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It is notable that the D7000 has a microphone port, which is missing on the D3100. Such an external microphone input can help to substantially improve the quality of audio recordings when a good external microphone is used.

Both the D7000 and the D3100 have been discontinued, but can regularly be found used on ebay. The D3100 was replaced by the Nikon D3200, while the D7000 was followed by the Nikon D7100. Further information on the features and operation of the D7000 and D3100 can be found, respectively, in the Nikon D7000 Manual (free pdf) or the online Nikon D3100 Manual.

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Review summary

So how do things add up? Is there a clear favorite between the Nikon D7000 and the Nikon D3100? Which camera is better? A synthesis of the relative strong points of each of the models is listed below.


Advantages of the Nikon D7000:

  • More detail: Offers more megapixels (16.1 vs 14.2MP) with a 7% higher linear resolution.
  • Better image quality: Scores substantially higher (13 points) in the DXO overall assessment.
  • More dynamic range: Captures a larger spectrum of light and dark details (2.6 EV of extra DR).
  • Better low-light sensitivity: Requires less light for good images (0.3 stops ISO advantage).
  • Better sound: Can connect to an external microphone for higher quality sound recording.
  • More complete view: Has a viewfinder with a larger field of view (100% vs 95%).
  • Larger viewfinder image: Features a viewfinder with a higher magnification (0.63x vs 0.53x).
  • Easier setting verification: Features an LCD display on top to control shooting parameters.
  • More detailed LCD: Has a higher resolution rear screen (921k vs 230k dots).
  • Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
  • Faster burst: Shoots at higher frequency (6 vs 3 flaps/sec) to capture the decisive moment.
  • Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
  • Longer lasting: Can take more shots (1050 versus 550) on a single battery charge.
  • Better sealing: Is weather sealed to enable shooting in dusty or wet environments.
  • Greater peace of mind: Features a second card slot as a backup in case of memory card failure.


Reasons to prefer the Nikon D3100:

  • More compact: Is smaller (124x96mm vs 132x105mm) and will fit more readily into a bag.
  • Less heavy: Has a lower weight (by 275g or 35 percent) and is thus easier to take along.
  • More affordable: Was introduced into a lower priced category (60 percent cheaper at launch).

If the count of relative strengths (bullet points above) is taken as a measure, the D7000 is the clear winner of the match-up (15 : 3 points). However, the relative importance of the various individual camera aspects will vary according to personal preferences and needs, so that you might like to apply corresponding weights to the particular features before making a decision on a new camera. A professional wildlife photographer will view the differences between cameras in a way that diverges from the perspective of a family photog, and a person interested in architecture has distinct needs from a sports shooter. Hence, the decision which camera is best and worth buying is often a very personal one.

D7000 15:03 D3100

How about other alternatives? Do the specifications of the Nikon D7000 and the Nikon D3100 place the cameras among the top in their class? Find out in the latest Best DSLR Camera listing whether the two cameras rank among the cream of the crop.

In any case, while the comparison of technical specifications can provide a useful overview of the capabilities of different cameras, it says little about, for example, the shooting experience and imaging performance of the D7000 and the D3100 in practical situations. User reviews, such as those found at amazon, can sometimes inform about these issues, but such feedback is often incomplete, inconsistent, and biased.

Expert reviews

This is where reviews by experts come in. The following table reports the overall ratings of the cameras as published by some of the major camera review sites (amateurphotographer [AP], cameralabs [CL], digitalcameraworld [DCW], dpreview [DPR], ephotozine [EPZ], photographyblog [PB]). As can be seen, the professional reviewers agree in many cases on the quality of different cameras, but sometimes their assessments diverge, reinforcing the earlier point that a camera decision is often a very personal choice.

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Expert Camera Reviews
# image  Camera 
 Model 
 AP 
 score 
 CL 
 score 
 DCW 
 score 
 DPR 
 score 
 EPZ 
 score 
 PB 
 score 
Camera
Launch
Launch
Price (USD)
Street
Price
1.
 
Nikon D70004/5....80/1004.5/54.5/5 Sep 2010 1,499ebay.com
2.
 
Nikon D31005/5+ +..72/1004.5/54.5/5 Aug 2010 599ebay.com
3.
 
Canon 60D5/5+..79/1004/54.5/5 Aug 2010 1,399ebay.com
4.
 
Canon 7D5/5+ +..84/1004.5/54.5/5 Sep 2009 1,699ebay.com
5.
 
Nikon D75004.5/5+ +4.5/586/1005/54.5/5 Apr 2017 1,299 amazon.com
6.
 
Nikon D71005/5+ +..85/1004.5/54.5/5 Feb 2013 1,199ebay.com
7.
 
Nikon D32005/5+ +..73/1004.5/54.5/5 Apr 2012 599ebay.com
8.
 
Nikon D51005/5+ +..76/1004.5/54.5/5 Apr 2011 749ebay.com
9.
 
Nikon D300S5/5+ +..82/1004/54.5/5 Jul 2009 1,799ebay.com
10.
 
Nikon D3000..+..72/1004/54.5/5 Jul 2009 599ebay.com
11.
 
Nikon D5000..+ +..75/1004/54.5/5 Apr 2009 749ebay.com
12.
 
Nikon D90..+ +..+ +4/54.5/5 Aug 2008 1,299ebay.com
13.
 
Nikon D300..+ +..+ +5/54.5/5 Aug 2007 1,799ebay.com
14.
 
Nikon D200..+ +..+ +o.. Nov 2005 1,699ebay.com
Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.
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The above review scores should be interpreted with care, though. The assessments were made in relation to similar cameras of the same technological generation. Thus, a score needs to be put into the context of the launch date and the launch price of the camera, and comparisons of ratings among very different cameras or across long time periods have little meaning. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

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Other camera comparisons

Did this review help to inform your camera decision process? In case you would like to check on the differences and similarities of other camera models, just make your choice using the following search menu. There is also a set of direct links to comparison reviews that other users of the CAM-parator app explored.

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    Specifications: Nikon D7000 vs Nikon D3100

    Below is a side-by-side comparison of the specs of the two cameras to facilitate a quick review of their differences and common features.

    Camera Specifications
    Camera Model Nikon D7000 Nikon D3100
    Camera Type Digital single lens reflex Digital single lens reflex
    Camera Lens Nikon F mount lenses Nikon F mount lenses
    Launch Date September 2010 August 2010
    Launch Price USD 1,499 USD 599
    Sensor Specs Nikon D7000 Nikon D3100
    Sensor Technology CMOS CMOS
    Sensor Format APS-C Sensor APS-C Sensor
    Sensor Size 23.6 x 15.7 mm 23.1 x 15.4 mm
    Sensor Area 370.52 mm2 355.74 mm2
    Sensor Diagonal 28.3 mm 27.8 mm
    Crop Factor 1.5x 1.5x
    Sensor Resolution 16.1 Megapixels 14.2 Megapixels
    Image Resolution 4928 x 3264 pixels 4608 x 3072 pixels
    Pixel Pitch 4.80 μm 5.01 μm
    Pixel Density 4.34 MP/cm2 3.98 MP/cm2
    Moiré control Anti-Alias filter Anti-Alias filter
    Movie Capability 1080/24p Video 1080/24p Video
    ISO Setting 100 - 6,400 ISO 100 - 3,200 ISO
    ISO Boost 100 - 25,600 ISO 100 - 12,800 ISO
    Image Processor EXPEED 2 EXPEED 2
    DXO Sensor Quality (score) 80 67
    DXO Color Depth (bits) 23.5 22.5
    DXO Dynamic Range (EV) 13.9 11.3
    DXO Low Light (ISO) 1167 919
    Screen Specs Nikon D7000 Nikon D3100
    Viewfinder Type Optical viewfinder Optical viewfinder
    Viewfinder Field of View 100% 95%
    Viewfinder Magnification 0.63x 0.53x
    Top-Level Screen Control Panel no Top Display
    LCD Framing Live View Live View
    Rear LCD Size 3.0inch 3.0inch
    LCD Resolution 921k dots 230k dots
    LCD Attachment Fixed screen Fixed screen
    Shooting Specs Nikon D7000 Nikon D3100
    Focus System Phase-detect AF Phase-detect AF
    Continuous Shooting 6 shutter flaps/s 3 shutter flaps/s
    Shutter Life Expectancy150 000 actuations100 000 actuations
    Time-Lapse PhotographyIntervalometer built-inno Intervalometer
    Fill Flash Built-in Flash Built-in Flash
    Storage Medium SDXC cards SDXC cards
    Single or Dual Card Slots Dual card slots Single card slot
    UHS card support no no
    Connectivity Specs Nikon D7000 Nikon D3100
    External Flash Hotshoe Hotshoe
    USB Connector USB 2.0 USB 2.0
    HDMI Port mini HDMI mini HDMI
    Microphone Port External MIC port no MIC socket
    Wifi Support no Wifi no Wifi
    Body Specs Nikon D7000 Nikon D3100
    Environmental SealingWeathersealed bodynot weather sealed
    Battery Type Nikon EN-EL15 Nikon EN-EL14
    Battery Life (CIPA)1050 shots per charge550 shots per charge
    Body Dimensions 132 x 105 x 77 mm
    (5.2 x 4.1 x 3.0 in)
    124 x 96 x 75 mm
    (4.9 x 3.8 x 3.0 in)
    Camera Weight 780 g (27.5 oz) 505 g (17.8 oz)
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