Nikon D7100 vs Olympus E-M1 III
The Nikon D7100 and the Olympus OM-D E-M1 Mark III are two enthusiast cameras that were announced, respectively, in February 2013 and February 2020. The D7100 is a DSLR, while the E-M1 III is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (D7100) and a Four Thirds (E-M1 III) sensor. The Nikon has a resolution of 24 megapixels, whereas the Olympus provides 20.2 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 Nikon D7100 and the Olympus OM-D E-M1 Mark III? 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 Nikon D7100 and the Olympus E-M1 III 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 measures are rounded to the nearest millimeter.
If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Olympus E-M1 III is notably smaller (16 percent) than the Nikon D7100. Moreover, the E-M1 III is markedly lighter (24 percent) than the D7100. In this context, it is worth noting that both cameras are splash and dust-proof and can, hence, be used in inclement weather conditions or harsh environments.
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. A larger imaging sensor will tend to go along with bigger and heavier lenses, although exceptions exist. You can compare the optics available for the two cameras in the Nikon Lens Catalog (D7100) and the Micro Four Thirds Lens Catalog (E-M1 III). Mirrorless cameras, such as the E-M1 III, have moreover the advantage that they can use many lenses from other systems via adapters, as they have a relatively short flange to focal plane distance.
Concerning battery life, the D7100 gets 950 shots out of its EN-EL15 battery, while the E-M1 III can take 420 images on a single charge of its BLH-1 power pack. The power pack in the E-M1 III can be charged via the USB port, which can be very convenient when travelling.
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.||Nikon D7100||136 mm||107 mm||76 mm||765 g||950||Y||Feb 2013||1,199|
|2.||Olympus E-M1 III||134 mm||91 mm||69 mm||580 g||420||Y||Feb 2020||1,799|
|3.||Canon 70D||139 mm||104 mm||79 mm||755 g||920||Y||Jul 2013||1,199|
|4.||Nikon D7500||136 mm||104 mm||73 mm||720 g||950||Y||Apr 2017||1,299|
|5.||Nikon D500||147 mm||115 mm||81 mm||860 g||1240||Y||Jan 2016||1,999|
|6.||Nikon D7200||136 mm||107 mm||76 mm||765 g||1110||Y||Mar 2015||1,199|
|7.||Nikon D750||141 mm||113 mm||78 mm||750 g||1230||Y||Sep 2014||2,299|
|8.||Nikon D3300||124 mm||98 mm||76 mm||430 g||700||n||Jan 2014||499|
|9.||Nikon D610||141 mm||113 mm||82 mm||850 g||900||Y||Oct 2013||1,999|
|10.||Nikon D600||141 mm||113 mm||82 mm||850 g||900||Y||Sep 2012||2,099|
|11.||Nikon D7000||132 mm||105 mm||77 mm||780 g||1050||Y||Sep 2010||1,499|
|12.||Olympus E-M5 III||125 mm||85 mm||50 mm||414 g||310||Y||Oct 2019||1,199|
|13.||Olympus E-M1X||144 mm||147 mm||75 mm||997 g||870||Y||Jan 2019||2,999|
|14.||Olympus E-M1 II||134 mm||91 mm||67 mm||574 g||440||Y||Sep 2016||1,999|
|15.||Panasonic G95||130 mm||94 mm||77 mm||536 g||290||Y||Apr 2019||999|
|16.||Panasonic G9||137 mm||97 mm||92 mm||658 g||400||Y||Nov 2017||1,699|
|17.||Sony RX10||129 mm||88 mm||102 mm||813 g||420||Y||Oct 2013||1,299|
|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 listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The D7100 was launched at a markedly lower price (by 33 percent) than the E-M1 III, 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.
Of the two cameras under consideration, the Nikon D7100 features an APS-C sensor and the Olympus E-M1 III a Four Thirds sensor. The sensor area in the E-M1 III is 39 percent smaller. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.5 and 2.0. The sensor in the D7100 has a native 3:2 aspect ratio, while the one in the E-M1 III offers a 4:3 aspect.
With 24MP, the D7100 offers a higher resolution than the E-M1 III (20.2MP), but the D7100 nevertheless has larger individual pixels (pixel pitch of 3.91μm versus 3.34μm for the E-M1 III) due to its larger sensor. However, the E-M1 III is a much more recent model (by 6 years and 11 months) than the D7100, and its sensor will have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixels. Coming back to sensor resolution, it should be mentioned that neither of the two cameras has an anti-alias filter installed, so they are able to capture all the detail the sensor resolves.
The resolution advantage of the Nikon D7100 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the D7100 for good quality output (200 dots per inch) amounts to 30 x 20 inches or 76.2 x 50.8 cm, for very good quality (250 dpi) 24 x 16 inches or 61 x 40.6 cm, and for excellent quality (300 dpi) 20 x 13.3 inches or 50.8 x 33.9 cm. The corresponding values for the Olympus E-M1 III are 25.9 x 19.4 inches or 65.8 x 49.4 cm for good quality, 20.7 x 15.6 inches or 52.7 x 39.5 cm for very good quality, and 17.3 x 13 inches or 43.9 x 32.9 cm for excellent quality prints.
The E-M1 III has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.
Unlike the D7100, the E-M1 III has the capacity to capture high quality composite images (80MP) by combining multiple shots after shifting its sensor by miniscule distances. This multi-shot, pixel-shift mode is most suitable for photography of stationary objects (landscapes, studio scenes).
The Nikon D7100 has a native sensitivity range from ISO 100 to ISO 6400, which can be extended to ISO 50-25600. The corresponding ISO settings for the Olympus OM-D E-M1 Mark III are ISO 200 to ISO 25600, with the possibility to increase the ISO range to 64-25600.
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 following table provides an overview of the physical sensor characteristics, as well as the sensor quality measurements for a selection of comparators.
| DXO |
|2.||Olympus E-M1 III||Four Thirds||20.2||5184||3888||4K/30p||..||..||..||..|
|7.||Nikon D750||Full Frame||24.2||6016||4016||1080/60p||24.8||14.5||2956||93|
|9.||Nikon D610||Full Frame||24.2||6016||4016||1080/30p||25.1||14.4||2925||94|
|10.||Nikon D600||Full Frame||24.2||6016||4016||1080/30p||25.1||14.2||2980||94|
|12.||Olympus E-M5 III||Four Thirds||20.2||5184||3888||4K/30p||..||..||..||..|
|13.||Olympus E-M1X||Four Thirds||20.2||5184||3888||4K/30p||..||..||..||..|
|14.||Olympus E-M1 II||Four Thirds||20.2||5184||3888||4K/30p||23.7||12.8||1312||80|
|15.||Panasonic G95||Four Thirds||20.2||5184||3888||4K/30p||..||..||..||..|
|16.||Panasonic G9||Four Thirds||20.2||5184||3888||4K/60p||..||..||..||..|
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 E-M1 III provides a better video resolution than the D7100. It can shoot movie footage at 4K/30p, while the Nikon is limited to 1080/60p.
Beyond body and sensor, cameras can and do differ across a range of features. For example, the E-M1 III has an electronic viewfinder (2360k dots), while the D7100 has an optical one. Both systems have their advantages, with the electronic viewfinder making it possible to project supplementary shooting information into the framing view, whereas the optical viewfinder offers lag-free viewing and a very clear framing image. The viewfinders of both cameras offer the same field of view (100%), but the viewfinder of the E-M1 III has a higher magnification than the one of the D7100 (0.83x vs 0.63x), 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 D7100 and Olympus E-M1 III in connection with corresponding information for a sample of similar cameras.
|2.||Olympus E-M1 III||2360||n||3.0||1037||swivel||Y||1/8000s||18.0||n||Y|
|12.||Olympus E-M5 III||2360||n||3.0||1040||swivel||Y||1/8000s||10.0||n||Y|
|14.||Olympus E-M1 II||2360||n||3.0||1037||swivel||Y||1/8000s||18.0||n||Y|
One difference between the cameras concerns the presence of an on-board flash. The D7100 has one, while the E-M1 III does not. While the built-in flash of the D7100 is not very powerful, it can at times be useful as a fill-in light.The E-M1 III has an articulated screen that can be turned to be front-facing. This characteristic will be appreciated by vloggers and photographers who are interested in taking selfies. In contrast, the D7100 does not have a selfie-screen.
The reported shutter speed information refers to the use of the mechanical shutter. Yet, some cameras only have an electronic shutter, while others have an electronic shutter in addition to a mechanical one. In fact, the E-M1 III is one of those camera that have an additional electronic shutter, which makes completely silent shooting possible. However, this mode is less suitable for photographing moving objects (risk of rolling shutter) or shooting under artificial light sources (risk of flickering).
The Nikon D7100 and the Olympus E-M1 III both have 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 D7100 and the E-M1 III write their files to SDXC cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. The E-M1 III supports UHS-II cards (on its first slot), while the D7100 can use UHS-I 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 Nikon D7100 and Olympus OM-D E-M1 Mark III and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
| NFC |
|2.||Olympus E-M1 III||Y||stereo||mono||Y||Y||micro||3.1||Y||-||Y|
|12.||Olympus E-M5 III||Y||stereo||mono||Y||-||micro||2.0||Y||-||Y|
|14.||Olympus E-M1 II||Y||stereo||mono||Y||Y||micro||3.0||Y||-||-|
It is notable that the E-M1 III offers wifi support, which can be a very convenient means to transfer image data to an off-camera location. In contrast, the D7100 does not provide wifi capability.
Studio photographers will appreciate that the Olympus E-M1 III (unlike the D7100) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
The E-M1 III is a recent model that features in the current product line-up of Olympus. In contrast, the D7100 has been discontinued (but can be found pre-owned on eBay). As a replacement in the same line of cameras, the D7100 was succeeded by the Nikon D7200. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Nikon and Olympus websites.
So what conclusions can be drawn? Is the Nikon D7100 better than the Olympus E-M1 III or vice versa? A synthesis of the relative strong points of each of the models is listed below.
Advantages of the Nikon D7100:
- More detail: Offers more megapixels (24 vs 20.2MP) with a 11% higher linear resolution.
- Brighter framing: Features an optical viewfinder for clear, lag-free composition.
- Easier setting verification: Features an LCD display on top to control shooting parameters.
- Larger screen: Has a bigger rear LCD (3.2" vs 3.0") for image review and settings control.
- More detailed LCD: Has a higher resolution rear screen (1229k vs 1037k dots).
- Longer lasting: Can take more shots (950 versus 420) on a single battery charge.
- Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
- More affordable: Was introduced into a lower priced category (33 percent cheaper at launch).
- More heavily discounted: Has been available for much longer (launched in February 2013).
Arguments in favor of the Olympus OM-D E-M1 Mark III:
- High quality composites: Can combine several shots after pixel-shifting its sensor.
- Better video: Provides higher definition movie capture (4K/30p vs 1080/60p).
- Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
- More framing info: Has an electronic viewfinder that displays shooting data.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.83x vs 0.63x).
- More flexible LCD: Has a swivel screen for odd-angle shots in portrait or landscape orientation.
- Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
- More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
- Faster burst: Shoots at higher frequency (18 vs 6 flaps/sec) to capture the decisive moment.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- More compact: Is smaller (134x91mm vs 136x107mm) and will fit more readily into a bag.
- Less heavy: Has a lower weight (by 185g or 24 percent) and is thus easier to take along.
- Easier travel charging: Can be conveniently charged via its USB port.
- Sharper images: Has stabilization technology built-in to reduce the impact of hand-shake.
- More legacy lens friendly: Can use many non-native lenses via adapters.
- Faster data transfer: Supports a more advanced USB protocol (3.1 vs 2.0).
- Easier file upload: Has wifi built in for automatic backup or image transfer to the web.
- Easier wireless transfer: Supports Bluetooth for image sharing without cables.
- Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
- Faster buffer clearing: Supports a more advanced SD data transfer standard (UHS-II vs UHS-I).
- More modern: Reflects 6 years and 11 months of technical progress since the D7100 launch.
If the count of relative strengths (bullet points above) is taken as a measure, the E-M1 III is the clear winner of the contest (21 : 9 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 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 Nikon D7100 and the Olympus E-M1 III place the cameras among the top in their class? Find out in the latest Best DSLR Camera and Best Mirrorless Interchangeable Lens Camera listings 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 D7100 or the E-M1 III 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], 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.||Nikon D7100||5/5||+ +||85/100||4.5/5||4.5/5||Feb 2013||1,199|
|2.||Olympus E-M1 III||5/5||..||83/100||4.5/5||4/5||Feb 2020||1,799|
|3.||Canon 70D||5/5||+ +||83/100||4.5/5||5/5||Jul 2013||1,199|
|4.||Nikon D7500||4.5/5||+ +||86/100||5/5||4.5/5||Apr 2017||1,299|
|5.||Nikon D500||5/5||+ +||91/100||4.5/5||5/5||Jan 2016||1,999|
|6.||Nikon D7200||4/5||+ +||84/100||4.5/5||4.5/5||Mar 2015||1,199|
|7.||Nikon D750||5/5||+ +||90/100||4.5/5||4.5/5||Sep 2014||2,299|
|8.||Nikon D3300||3/5||+||77/100||4.5/5||4.5/5||Jan 2014||499|
|9.||Nikon D610||4/5||+ +||87/100||4.5/5||4.5/5||Oct 2013||1,999|
|10.||Nikon D600||4/5||+ +||87/100||5/5||4.5/5||Sep 2012||2,099|
|11.||Nikon D7000||4/5||..||80/100||4.5/5||4.5/5||Sep 2010||1,499|
|12.||Olympus E-M5 III||5/5||+||82/100||4.5/5||4.5/5||Oct 2019||1,199|
|13.||Olympus E-M1X||4.5/5||o||..||4.5/5||..||Jan 2019||2,999|
|14.||Olympus E-M1 II||5/5||+ +||85/100||4.5/5||4.5/5||Sep 2016||1,999|
|15.||Panasonic G95||4.5/5||+||83/100||4.5/5||4.5/5||Apr 2019||999|
|16.||Panasonic G9||..||+ +||85/100||5/5||5/5||Nov 2017||1,699|
|17.||Sony RX10||5/5||+||80/100||4.5/5||4.5/5||Oct 2013||1,299|
|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. Also, please note that some of the review sites have changed their methodology and reporting over time.
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: Nikon D7100 vs Olympus E-M1 III
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||Nikon D7100||Olympus E-M1 III|
|Camera Type||Digital single lens reflex||Mirrorless system camera|
|Camera Lens||Nikon F mount lenses||Micro Four Thirds lenses|
|Launch Date||February 2013||February 2020|
|Launch Price||USD 1,199||USD 1,799|
|Sensor Specs||Nikon D7100||Olympus E-M1 III|
|Sensor Format||APS-C Sensor||Four Thirds Sensor|
|Sensor Size||23.5 x 15.6 mm||17.3 x 13.0 mm|
|Sensor Area||366.6 mm2||224.9 mm2|
|Sensor Diagonal||28.2 mm||21.6 mm|
|Sensor Resolution||24 Megapixels||20.2 Megapixels|
|Image Resolution||6000 x 4000 pixels||5184 x 3888 pixels|
|Pixel Pitch||3.91 μm||3.34 μm|
|Pixel Density||6.55 MP/cm2||8.96 MP/cm2|
|Moiré control||no AA filter||no AA filter|
|Movie Capability||1080/60p Video||4K/30p Video|
|ISO Setting||100 - 6,400 ISO||200 - 25,600 ISO|
|ISO Boost||50 - 25,600 ISO||64 - 25,600 ISO|
|Image Processor||EXPEED 4||TruePic IX|
|DXO Sensor Quality (score)||83||..|
|DXO Color Depth (bits)||24.2||..|
|DXO Dynamic Range (EV)||13.7||..|
|DXO Low Light (ISO)||1256||..|
|Screen Specs||Nikon D7100||Olympus E-M1 III|
|Viewfinder Type||Optical viewfinder||Electronic viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||2360k dots|
|Top-Level Screen||Control Panel||no Top Display|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.2inch||3.0inch|
|LCD Resolution||1229k dots||1037k dots|
|LCD Attachment||Fixed screen||Swivel screen|
|Touch Input||no Touchscreen||Touchscreen|
|Shooting Specs||Nikon D7100||Olympus E-M1 III|
|Focus System||Phase-detect AF||On-Sensor Phase-detect|
|Manual Focusing Aid||no Peaking Feature||Focus Peaking|
|Max Shutter Speed (mechanical)||1/8000s||1/8000s|
|Continuous Shooting||6 shutter flaps/s||18 shutter flaps/s|
|Shutter Life Expectancy||150 000 actuations||400 000 actuations|
|Electronic Shutter||no E-Shutter||up to 1/32000s|
|Time-Lapse Photography||Intervalometer built-in||Intervalometer built-in|
|Image Stabilization||Lens stabilization only||In-body stabilization|
|Fill Flash||Build-in Flash||no On-Board Flash|
|Storage Medium||SDXC cards||SDXC cards|
|Second Storage Option||Dual card slots||Dual card slots|
|UHS card support||UHS-I||Single UHS-II|
|Connectivity Specs||Nikon D7100||Olympus E-M1 III|
|Studio Flash||no PC Sync||PC Sync socket|
|USB Connector||USB 2.0||USB 3.1|
|HDMI Port||mini HDMI||micro HDMI|
|Microphone Port||External MIC port||External MIC port|
|Headphone Socket||Headphone port||Headphone port|
|Wifi Support||no Wifi||Wifi built-in|
|Bluetooth Support||no Bluetooth||Bluetooth built-in|
|Body Specs||Nikon D7100||Olympus E-M1 III|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||950 shots per charge||420 shots per charge|
|In-Camera Charging||no USB charging||USB charging|
136 x 107 x 76 mm
(5.4 x 4.2 x 3.0 in)
134 x 91 x 69 mm
(5.3 x 3.6 x 2.7 in)
|Camera Weight||765 g (27.0 oz)||580 g (20.5 oz)|
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