Canon 7D vs Nikon D3100
The Canon EOS 7D and the Nikon D3100 are two digital cameras that were revealed to the public, respectively, in September 2009 and August 2010. Both are DSLR (Digital Single Lens Reflex) cameras that are equipped with an APS-C sensor. The Canon has a resolution of 17.9 megapixels, whereas the Nikon provides 14.2 MP.
Below is an overview of the main specs of the two cameras as a starting point for the comparison.
Going beyond this snapshot of core features and characteristics, what are the differences between the Canon EOS 7D 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.
The physical size and weight of the Canon 7D and the Nikon D3100 are illustrated in the side-by-side display below. The two cameras are presented according to their relative size. Three successive views from the front, the top, and the rear are shown. All width, height and depth dimensions are rounded to the nearest millimeter.
The D3100 can be obtained in two different colors (black, red), while the 7D is only available in black.
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 (28 percent) than the Canon 7D. Moreover, the D3100 is substantially lighter (41 percent) than the 7D. It is worth mentioning in this context that the 7D 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. Yet, since both cameras are based around an APS-C sensor, their respective lenses will tend to have similar dimensions and heft. You can compare the optics available for the two cameras in the Canon EF Lens Catalog (7D) and the Nikon Lens Catalog (D3100).
The adjacent table lists the principal physical characteristics of the two cameras alongside a wider set of alternatives. 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.
|1.||Canon 7D||148 mm||111 mm||74 mm||860 g||800||Y||Sep 2009||1,699|
|2.||Nikon D3100||124 mm||96 mm||75 mm||505 g||550||n||Aug 2010||599|
|3.||Canon 7D II||149 mm||112 mm||78 mm||910 g||670||Y||Sep 2014||1,799|
|4.||Canon 70D||139 mm||104 mm||79 mm||755 g||920||Y||Jul 2013||1,199|
|5.||Canon 60D||145 mm||106 mm||79 mm||755 g||1100||Y||Aug 2010||1,399|
|6.||Canon T2i||129 mm||98 mm||62 mm||530 g||440||n||Feb 2010||699|
|7.||Canon T1i||129 mm||98 mm||62 mm||520 g||400||n||Mar 2009||799|
|8.||Canon 5D Mark II||152 mm||114 mm||75 mm||850 g||850||Y||Sep 2008||3,499|
|9.||Canon 50D||146 mm||108 mm||74 mm||822 g||800||Y||Aug 2008||1,299|
|10.||Canon 30D||144 mm||106 mm||74 mm||785 g||750||n||Feb 2006||1,399|
|11.||Canon 20D||144 mm||106 mm||72 mm||770 g||700||n||Aug 2004||1,499|
|12.||Nikon D3200||125 mm||96 mm||77 mm||505 g||540||n||Apr 2012||599|
|13.||Nikon D5100||128 mm||97 mm||79 mm||560 g||660||n||Apr 2011||749|
|14.||Nikon D7000||132 mm||105 mm||77 mm||780 g||1050||Y||Sep 2010||1,499|
|15.||Nikon D3000||126 mm||97 mm||64 mm||536 g||500||n||Jul 2009||599|
|16.||Nikon D5000||127 mm||104 mm||80 mm||590 g||510||n||Apr 2009||749|
|Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.|
Any camera decision will obviously take relative prices into account. The manufacturer’s suggested retail prices give an idea on the placement of the camera in the maker’s lineup and the broader market. The D3100 was launched at a markedly lower price (by 65 percent) than the 7D, 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.
The size of the sensor inside a digital camera is one of the key determinants of image quality. A large sensor will generally have larger individual pixels that offer better low-light sensitivity, provide wider dynamic range, and have richer color-depth than smaller pixels in a sensor of the same technological generation. Moreover, a large sensor camera will give the photographer more control over depth-of-field in the image and, thus, the ability to better isolate a subject from the background. On the downside, larger sensors tend to be associated with larger, more expensive camera bodies 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 7 percent bigger. As a result of these sensor size differences, the cameras have format factors, respectively, of 1.6 (7D) and 1.5. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.
Despite having a smaller sensor, the Canon 7D offers a higher resolution of 17.9 megapixels, compared with 14.2 MP of the Nikon D3100. This megapixels advantage comes at the cost of a higher pixel density and a smaller size of the individual pixel (with a pixel pitch of 4.31μm versus 5.01μm for the D3100). Moreover, it should be noted that the D3100 is a somewhat more recent model (by 11 months) than the 7D, and its sensor might have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixel-units.
The resolution advantage of the Canon 7D implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the 7D for good quality output (200 dots per inch) amounts to 25.9 x 17.3 inches or 65.8 x 43.9 cm, for very good quality (250 dpi) 20.7 x 13.8 inches or 52.7 x 35.1 cm, and for excellent quality (300 dpi) 17.3 x 11.5 inches or 43.9 x 29.3 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 Canon EOS 7D has a native sensitivity range from ISO 100 to ISO 6400, which can be extended to ISO 100-12800. 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.
For many cameras, data on sensor performance has been reported by DXO Mark. This service is based on lab testing and assigns an overall score to each camera sensor, as well as ratings for dynamic range ("DXO Landscape"), color depth ("DXO Portrait"), and low-light sensitivity ("DXO Sports"). The Overall DXO ratings for the two cameras under consideration are close, suggesting that they provide similar imaging performance. The following table provides an overview of the physical sensor characteristics, as well as the sensor quality measurements for a selection of comparators.
|3.||Canon 7D II||APS-C||20.0||5472||3648||1080/60p||22.4||11.8||1082||70|
|8.||Canon 5D Mark II||Full Frame||21.0||5616||3744||1080/30p||23.7||11.9||1815||79|
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, but the 7D provides a higher frame rate than the D3100. It can shoot video footage at 1080/30p, while the Nikon is limited to 1080/24p.
Beyond body and sensor, cameras can and do differ across a range of features. The 7D 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 7D 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 7D 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 adjacent table lists some of the other core features of the Canon 7D and Nikon D3100 along with similar information for a selection of comparators.
|1.||Canon 7D||optical||Y||3.0 / 920||fixed||n||1/8000s||8.0||Y||n|
|2.||Nikon D3100||optical||n||3.0 / 230||fixed||n||1/4000s||3.0||Y||n|
|3.||Canon 7D II||optical||Y||3.0 / 1040||fixed||n||1/8000s||10.0||Y||n|
|4.||Canon 70D||optical||Y||3.0 / 1040||swivel||Y||1/8000s||7.0||Y||n|
|5.||Canon 60D||optical||Y||3.0 / 1040||swivel||n||1/8000s||5.3||Y||n|
|6.||Canon T2i||optical||n||3.0 / 1040||fixed||n||1/4000s||3.7||Y||n|
|7.||Canon T1i||optical||n||3.0 / 920||fixed||n||1/4000s||3.4||Y||n|
|8.||Canon 5D Mark II||optical||Y||3.0 / 920||fixed||n||1/8000s||3.9||n||n|
|9.||Canon 50D||optical||Y||3.0 / 920||fixed||n||1/8000s||6.3||Y||n|
|10.||Canon 30D||optical||Y||2.5 / 230||fixed||n||1/8000s||5.0||Y||n|
|11.||Canon 20D||optical||Y||1.8 / 118||fixed||n||1/8000s||5.0||Y||n|
|12.||Nikon D3200||optical||n||3.0 / 921||fixed||n||1/4000s||4.0||Y||n|
|13.||Nikon D5100||optical||n||3.0 / 921||swivel||n||1/4000s||4.0||Y||n|
|14.||Nikon D7000||optical||Y||3.0 / 921||fixed||n||1/8000s||6.0||Y||n|
|15.||Nikon D3000||optical||n||3.0 / 230||fixed||n||1/4000s||3.0||Y||n|
|16.||Nikon D5000||optical||n||2.7 / 230||full-flex||n||1/4000s||4.0||Y||n|
One feature that is present on the 7D, 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 7D writes its imaging data to Compact Flash cards, while the D3100 uses SDXC cards.
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 Canon EOS 7D and Nikon D3100 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
Mic / Speaker
|1.||Canon 7D||Y||mono / -||Y||-||mini||2.0||-||-||-|
|2.||Nikon D3100||Y||mono / mono||-||-||mini||2.0||-||-||-|
|3.||Canon 7D II||Y||stereo / mono||Y||Y||mini||3.0||-||-||-|
|4.||Canon 70D||Y||stereo / mono||Y||-||mini||2.0||Y||-||-|
|5.||Canon 60D||Y||mono / mono||Y||-||mini||2.0||-||-||-|
|6.||Canon T2i||Y||stereo / -||Y||-||mini||2.0||-||-||-|
|7.||Canon T1i||Y||mono / mono||-||-||mini||2.0||-||-||-|
|8.||Canon 5D Mark II||Y||mono / mono||Y||-||mini||2.0||-||-||-|
|9.||Canon 50D||Y||- / -||-||-||mini||2.0||-||-||-|
|10.||Canon 30D||Y||- / -||-||-||-||2.0||-||-||-|
|11.||Canon 20D||Y||- / -||-||-||-||1.1||-||-||-|
|12.||Nikon D3200||Y||mono / mono||Y||-||mini||2.0||-||-||-|
|13.||Nikon D5100||Y||mono / mono||Y||-||mini||2.0||-||-||-|
|14.||Nikon D7000||Y||mono / mono||Y||-||mini||2.0||-||-||-|
|15.||Nikon D3000||Y||- / -||-||-||-||2.0||-||-||-|
|16.||Nikon D5000||Y||mono / mono||-||-||mini||2.0||-||-||-|
It is notable that the 7D 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.
Studio photographers will appreciate that the Canon 7D (unlike the D3100) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
Both the 7D and the D3100 have been discontinued, but can regularly be found used on eBay. The 7D was replaced by the Canon 7D Mark II, while the D3100 was followed by the Nikon D3200. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Canon and Nikon websites.
So what conclusions can be drawn? Is the Canon 7D better than the Nikon D3100 or vice versa? A synthesis of the relative strong points of each of the models is listed below.
Advantages of the Canon EOS 7D:
- More detail: Offers more megapixels (17.9 vs 14.2MP) with a 12% higher linear resolution.
- Better video: Provides higher movie framerates (1080/30p versus 1080/24p).
- 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 (920k vs 230k dots).
- Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
- Faster burst: Shoots at higher frequency (8 vs 3 flaps/sec) to capture the decisive moment.
- Longer lasting: Can take more shots (800 versus 550) on a single battery charge.
- Better sealing: Is weather sealed to enable shooting in dusty or wet environments.
- Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
- More heavily discounted: Has been on the market for longer (launched in September 2009).
Arguments in favor of the Nikon D3100:
- More compact: Is smaller (124x96mm vs 148x111mm) and will fit more readily into a bag.
- Less heavy: Has a lower weight (by 355g or 41 percent) and is thus easier to take along.
- More affordable: Was introduced into a lower priced category (65 percent cheaper at launch).
- More modern: Was introduced somewhat (11 months) more recently.
If the count of relative strengths (bullet points above) is taken as a measure, the 7D is the clear winner of the match-up (13 : 4 points). However, the relevance of individual strengths will vary across photographers, so that you might want to apply your own weighing scheme to the summary points when reflecting and deciding on a new camera. A professional wedding photographer will view the differences between cameras in a way that diverges from the perspective of a travel photog, and a person interested in cityscapes has distinct needs from a macro shooter. Hence, the decision which camera is best and worth buying is often a very personal one.
How about other alternatives? Do the specifications of the Canon 7D 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 the spec-sheets of cameras can offer a general idea of their imaging potential, it remains incomplete and does no justice, for example, to the way the 7D or the D3100 perform in practice. At times, user reviews, such as those published at amazon, address these issues in a useful manner, but such feedback is on many occasions incomplete, inconsistent, and unreliable.
This is why expert reviews are important. The adjacent summary-table relays the overall verdicts of several of the most popular 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.
|1.||Canon 7D||5/5||+ +||..||84/100||4.5/5||4.5/5||Sep 2009||1,699|
|2.||Nikon D3100||5/5||+ +||..||72/100||4.5/5||4.5/5||Aug 2010||599|
|3.||Canon 7D II||4.5/5||+||3.5/5||84/100||4/5||4.5/5||Sep 2014||1,799|
|4.||Canon 70D||5/5||+ +||..||83/100||4.5/5||5/5||Jul 2013||1,199|
|5.||Canon 60D||5/5||+||..||79/100||4/5||4.5/5||Aug 2010||1,399|
|6.||Canon T2i||..||+ +||..||77/100||4/5||4.5/5||Feb 2010||699|
|7.||Canon T1i||..||+ +||..||74/100||4.5/5||4.5/5||Mar 2009||799|
|8.||Canon 5D Mark II||4/5||91/100||..||79/100||4/5||..||Sep 2008||3,499|
|9.||Canon 50D||..||+ +||..||+ +||4.5/5||4.5/5||Aug 2008||1,299|
|10.||Canon 30D||..||+ +||..||+ +||o||..||Feb 2006||1,399|
|11.||Canon 20D||..||..||..||+ +||..||..||Aug 2004||1,499|
|12.||Nikon D3200||5/5||+ +||..||73/100||4.5/5||4.5/5||Apr 2012||599|
|13.||Nikon D5100||5/5||+ +||..||76/100||4.5/5||4.5/5||Apr 2011||749|
|14.||Nikon D7000||4/5||..||..||80/100||4.5/5||4.5/5||Sep 2010||1,499|
|15.||Nikon D3000||..||+||..||72/100||4/5||4.5/5||Jul 2009||599|
|16.||Nikon D5000||..||+ +||..||75/100||4/5||4.5/5||Apr 2009||749|
|Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.|
The above review scores should be interpreted with care, though. The assessments were made in relation to similar cameras of the same technological generation. A score, therefore, has to be seen in close connection to the price and market introduction time of the camera, and comparing ratings of very distinct cameras or ones that are far apart in terms of their release date have little meaning. It should also be noted that some of the review sites have over time altered the way they render their verdicts.
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. Alternatively, you can follow any of the listed hyperlinks for comparisons that others found interesting.
Specifications: Canon 7D 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 Model||Canon 7D||Nikon D3100|
|Camera Type||Digital single lens reflex||Digital single lens reflex|
|Camera Lens||Canon EF mount lenses||Nikon F mount lenses|
|Launch Date||September 2009||August 2010|
|Launch Price||USD 1,699||USD 599|
|Sensor Specs||Canon 7D||Nikon D3100|
|Sensor Format||APS-C Sensor||APS-C Sensor|
|Sensor Size||22.3 x 14.9 mm||23.1 x 15.4 mm|
|Sensor Area||332.27 mm2||355.74 mm2|
|Sensor Diagonal||26.8 mm||27.8 mm|
|Sensor Resolution||17.9 Megapixels||14.2 Megapixels|
|Image Resolution||5184 x 3456 pixels||4608 x 3072 pixels|
|Pixel Pitch||4.31 μm||5.01 μm|
|Pixel Density||5.39 MP/cm2||3.98 MP/cm2|
|Moiré control||Anti-Alias filter||Anti-Alias filter|
|Movie Capability||1080/30p Video||1080/24p Video|
|ISO Setting||100 - 6,400 ISO||100 - 3,200 ISO|
|ISO Boost||100 - 12,800 ISO||100 - 12,800 ISO|
|Image Processor||DIGIC 4 (Dual)||EXPEED 2|
|DXO Sensor Quality (score)||66||67|
|DXO Color Depth (bits)||22.0||22.5|
|DXO Dynamic Range (EV)||11.7||11.3|
|DXO Low Light (ISO)||854||919|
|Screen Specs||Canon 7D||Nikon D3100|
|Viewfinder Type||Optical viewfinder||Optical viewfinder|
|Viewfinder Field of View||100%||95%|
|Top-Level Screen||Control Panel||no Top Display|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.0inch||3.0inch|
|LCD Resolution||920k dots||230k dots|
|LCD Attachment||Fixed screen||Fixed screen|
|Shooting Specs||Canon 7D||Nikon D3100|
|Focus System||Phase-detect AF||Phase-detect AF|
|Continuous Shooting||8 shutter flaps/s||3 shutter flaps/s|
|Shutter Life Expectancy||150 000 actuations||100 000 actuations|
|Fill Flash||Built-in Flash||Built-in Flash|
|Storage Medium||CF cards||SDXC cards|
|Second Storage Option||Single card slot||Single card slot|
|Connectivity Specs||Canon 7D||Nikon D3100|
|Studio Flash||PC Sync socket||no PC Sync|
|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||Canon 7D||Nikon D3100|
|Environmental Sealing||Weathersealed body||not weather sealed|
|Battery Life (CIPA)||800 shots per charge||550 shots per charge|
148 x 111 x 74 mm
(5.8 x 4.4 x 2.9 in)
124 x 96 x 75 mm
(4.9 x 3.8 x 3.0 in)
|Camera Weight||860 g (30.3 oz)||505 g (17.8 oz)|
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