Nikon D7100 versus Sony A9
The Nikon D7100 and the Sony Alpha A9 are two digital cameras that were announced, respectively, in February 2013 and April 2017. The D7100 is a DSLR, while the A9 is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (D7100) and a full frame (A9) sensor. Both cameras offer a resolution of 24 megapixel. Read on to find out how these two cameras compare with respect to their size, their sensors, their features, and their reception by expert reviewers.
Body comparison: Nikon D7100 vs Sony A9
The physical size and weight of the Nikon D7100 and the Sony A9 are illustrated in the side-by-side display below. Three consecutive views from the front, the top, and the rear side are shown. All size dimensions are rounded to the nearest millimeter. You can also use the toggle button to switch to a percentage comparison if you prefer that the measures are being expressed in relative terms (in this case, the camera on the left – the D7100 – represents 100 percent across all the size and weight measures).
If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony A9 is notably smaller (16 percent) than the Nikon D7100. Moreover, the A9 is markedly lighter (12 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 find an overview of optics for the two cameras in the Nikon Lens Catalog (D7100) and the Sony FE Lens Catalog (A9). Mirrorless cameras, such as the A9, 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.
The table below summarizes the key physical specs of the two cameras alongside a broader set of comparators. If you want to switch the focus of the display and review another camera pair, just select a new right or left comparator from among the camera models in the table. Alternatively, you can also move across to the CAM-parator tool and choose from the broad selection of possible camera comparisons there.
|Camera Body Specifications
|Nikon D7100 (⇒ rgt)||136 mm||107 mm||76 mm||765 g||950||YES||2013||1,199||discont.||check|
|Sony A9 (⇒ lft)||127 mm||96 mm||63 mm||673 g||650||YES||2017||4,499||latest||check|
|Canon 70D (⇒ lft | rgt)||139 mm||104 mm||79 mm||755 g||920||YES||2013||1,199||discont.||check|
|Nikon D7500 (⇒ lft | rgt)||136 mm||104 mm||73 mm||720 g||950||YES||2017||1,299||latest||check|
|Nikon D500 (⇒ lft | rgt)||147 mm||115 mm||81 mm||860 g||1240||YES||2016||1,999||latest||check|
|Nikon D7200 (⇒ lft | rgt)||136 mm||107 mm||76 mm||765 g||1110||YES||2015||1,199||discont.||check|
|Nikon D3300 (⇒ lft | rgt)||124 mm||98 mm||76 mm||430 g||700||no||2014||499||discont.||check|
|Nikon D750 (⇒ lft | rgt)||141 mm||113 mm||78 mm||750 g||1230||YES||2014||2,299||latest||check|
|Nikon D610 (⇒ lft | rgt)||141 mm||113 mm||82 mm||850 g||900||YES||2013||1,999||latest||check|
|Nikon D600 (⇒ lft | rgt)||141 mm||113 mm||82 mm||850 g||900||YES||2012||2,099||discont.||check|
|Nikon D7000 (⇒ lft | rgt)||132 mm||105 mm||77 mm||780 g||1050||YES||2010||1,499||discont.||check|
|Sony A7 III (⇒ lft | rgt)||127 mm||96 mm||74 mm||650 g||610||YES||2018||1,999||latest||check|
|Sony A7R III (⇒ lft | rgt)||127 mm||96 mm||74 mm||650 g||650||YES||2017||3,199||latest||check|
|Sony A7R II (⇒ lft | rgt)||127 mm||96 mm||60 mm||625 g||290||YES||2015||3,199||discont.||check|
|Sony A7S II (⇒ lft | rgt)||127 mm||96 mm||60 mm||627 g||370||YES||2015||2,999||latest||check|
|Sony A7 II (⇒ lft | rgt)||127 mm||96 mm||60 mm||599 g||350||YES||2014||1,999||discont.||check|
|Sony RX10 (⇒ lft | rgt)||129 mm||88 mm||102 mm||813 g||420||YES||2013||1,299||discont.||check|
The price is, of course, an important factor in any camera decision. 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 73 percent) than the A9, 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: Nikon D7100 vs Sony A9
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 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 more expensive and lead to bigger and heavier cameras and lenses.
Of the two cameras under consideration, the Nikon D7100 features an APS-C sensor and the Sony A9 a full frame sensor. The sensor area in the A9 is 131 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.5 and 1.0. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.
Even though the A9 has a larger sensor, both cameras offer the same resolution of 24 megapixel. This implies that the A9 has a lower pixel density and larger individual pixels (with a pixel pitch of 5.94μm versus 3.91μm for the D7100), which gives it a potential advantage in terms of light gathering capacity. In addition, the A9 is much more recent (by 4 years and 1 month) than the D7100, and its sensor will have benefitted from technological advances during this time. Coming back to sensor resolution, it should be mentioned that the D7100 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.
Consistent information on actual sensor performance is available from DXO Mark for most cameras. 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 consideration, the A9 has a markedly higher DXO score than the D7100 (overall score 9 points higher), which will translate into better image quality. The advantage is based on 0.7 bits higher color depth, 0.4 EV of lower dynamic range, and 1.5 stops in additional low light sensitivity. The table below summarizes the physical sensor characteristics and sensor quality findings and compares them across a set of similar cameras.
|Nikon D7100 (⇒ rgt)||APS-C||24.0||6000||4000||1080/60p||24.2||13.7||1256||83|
|Sony A9 (⇒ lft)||Full Frame||24.0||6000||4000||4K/30p||24.9||13.3||3517||92|
|Canon 70D (⇒ lft | rgt)||APS-C||20.0||5472||3648||1080/30p||22.5||11.6||926||68|
|Nikon D7500 (⇒ lft | rgt)||APS-C||20.7||5568||3712||4K/30p||24.3||14.0||1483||86|
|Nikon D500 (⇒ lft | rgt)||APS-C||20.7||5568||3712||4K/30p||24.0||14.0||1324||83|
|Nikon D7200 (⇒ lft | rgt)||APS-C||24.0||6000||4000||1080/60p||24.5||14.6||1333||87|
|Nikon D3300 (⇒ lft | rgt)||APS-C||24.0||6000||4000||1080/60p||24.3||12.8||1385||82|
|Nikon D750 (⇒ lft | rgt)||Full Frame||24.2||6016||4016||1080/60p||24.8||14.5||2956||93|
|Nikon D610 (⇒ lft | rgt)||Full Frame||24.2||6016||4016||1080/30p||25.1||14.4||2925||94|
|Nikon D600 (⇒ lft | rgt)||Full Frame||24.2||6016||4016||1080/30p||25.1||14.2||2980||94|
|Nikon D7000 (⇒ lft | rgt)||APS-C||16.1||4928||3264||10800/24p||23.5||13.9||1167||80|
|Sony A7 III (⇒ lft | rgt)||Full Frame||24.0||6000||4000||4K/30p||25.0||14.7||3730||96|
|Sony A7R III (⇒ lft | rgt)||Full Frame||42.2||7952||5304||4K/30p||26.0||14.7||3523||100|
|Sony A7R II (⇒ lft | rgt)||Full Frame||42.2||7952||5304||4K/30p||26.0||13.9||3434||98|
|Sony A7S II (⇒ lft | rgt)||Full Frame||12.0||4240||2832||4K/30p||23.6||13.3||2993||85|
|Sony A7 II (⇒ lft | rgt)||Full Frame||24.0||6000||4000||1080/60p||24.9||13.6||2449||90|
|Sony RX10 (⇒ lft | rgt)||1-inch||20.0||5472||3648||1080/60p||22.9||12.6||474||69|
Many modern cameras are not only capable of taking still images, but also of capturing video footage. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, but the A9 provides a better video resolution than the D7100. It can shoot movie footage at 4K/30p, while the Nikon is limited to 1080/60p.
Feature comparison: Nikon D7100 vs Sony A9
Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A9 has an electronic viewfinder (3686k 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 table below summarizes some of the other core capabilities of the Nikon D7100 and Sony A9 in connection with corresponding information for a sample of similar cameras. The full specs-sheets can be found in the camera manual or, for example, in the dpreview camera hub.
|Nikon D7100 (⇒ rgt)||optical||YES||3.2||1229||fixed||no||8000||6.0||12||no|
|Sony A9 (⇒ lft)||3686||no||3.0||1440||tilting||YES||8000||20.0||no||YES|
|Canon 70D (⇒ lft | rgt)||optical||YES||3.0||1040||swivel||YES||8000||7.0||12||no|
|Nikon D7500 (⇒ lft | rgt)||optical||YES||3.2||922||tilting||YES||8000||8.0||12||no|
|Nikon D500 (⇒ lft | rgt)||optical||YES||3.2||2359||tilting||YES||8000||10.0||no||no|
|Nikon D7200 (⇒ lft | rgt)||optical||YES||3.2||1229||fixed||no||8000||6.0||12||no|
|Nikon D3300 (⇒ lft | rgt)||optical||no||3.0||921||fixed||no||4000||5.0||12||no|
|Nikon D750 (⇒ lft | rgt)||optical||YES||3.2||1229||tilting||no||4000||6.0||12||no|
|Nikon D610 (⇒ lft | rgt)||optical||YES||3.2||921||fixed||no||4000||6.0||12||no|
|Nikon D600 (⇒ lft | rgt)||optical||YES||3.0||921||fixed||no||4000||5.5||12||no|
|Nikon D7000 (⇒ lft | rgt)||optical||YES||3.0||921||fixed||no||8000||6.0||12||no|
|Sony A7 III (⇒ lft | rgt)||2359||no||3.0||922||tilting||YES||8000||10||no||YES|
|Sony A7R III (⇒ lft | rgt)||3686||no||3.0||1440||tilting||YES||8000||10.0||no||YES|
|Sony A7R II (⇒ lft | rgt)||2400||no||3.0||1229||tilting||no||8000||5.0||no||YES|
|Sony A7S II (⇒ lft | rgt)||2400||no||3.0||1229||tilting||no||8000||5.0||no||YES|
|Sony A7 II (⇒ lft | rgt)||2400||no||3.0||1230||tilting||no||8000||5.0||no||YES|
|Sony RX10 (⇒ lft | rgt)||1440||YES||3.0||1229||tilting||no||3200||10.0||10.2||YES|
The A9 is a current model that online retailers, such as amazon, will have in stock. In contrast, the D7100 has been discontinued (but it can be found pre-owned on eBay). As a replacement in the same line of cameras, the D7100 was succeeded by the Nikon D7200.
Review summary: Nikon D7100 vs Sony A9
So what is the bottom line? Which of the two cameras – the Nikon D7100 or the Sony A9 – has the upper hand? Below is a summary of the relative strengths of each of the two contestants.
Advantages of the Nikon D7100:
- Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
- Brighter framing: Features an optical viewfinder for clear, lag-free composition.
- Easier setting verification: Has 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.
- Longer lasting: Can take more shots (950 versus 650) 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 (73 percent cheaper at launch).
- More heavily discounted: Has been available for much longer (launched in February 2013).
Reasons to prefer the Sony Alpha A9:
- Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
- Better image quality: Scores markedly higher (9 points) in the DXO overall evaluation.
- Better low-light sensitivity: Can shoot in dim conditions (1.5 stops ISO advantage).
- Better video: Provides higher definition movie capture (4K/30p vs 1080/60p).
- More framing info: Has an electronic viewfinder that displays shooting data.
- More detailed LCD: Has a higher resolution rear screen (1440k vs 1229k dots).
- More flexible LCD: Has a tilting screen for odd-angle shots in landscape orientation.
- Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
- Faster burst: Shoots at higher frequency (20 vs 6 flaps/sec) to capture the decisive moment.
- More compact: Is smaller (127x96mm vs 136x107mm) and will fit more readily into a bag.
- Less heavy: Has a lower weight (by 92g or 12 percent) and is thus easier to take along.
- More legacy lens friendly: Can use many non-native lenses via adapters.
- Sharper images: Has stabilization technology build-in to reduce the impact of hand-shake.
- More modern: Reflects 4 years and 1 month of technical progress since the D7100 launch.
If the count of individual advantages (bullet points above) is taken as a guide, the A9 is the clear winner of the contest (14 : 8 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.
In any case, while the comparison of technical specifications can provide a useful overview of the capabilities of different cameras, it remains partial and cannot reveal, for example, the handling experience and imaging performance when actually working with the D7100 or the A9. User reviews, such as those found at amazon, can sometimes inform about these issues, but such feedback is often incomplete, inconsistent, and biased. This is why expert reviews are important. The following table reports the overall rankings of the cameras as published by some of the major camera review sites. You can find the full text of the reviews, respectively, at cameralabs.com, dpreview.com, ephotozine.com, imaging-resource.com, and photographyblog.com.
|Nikon D7100 (⇒ rgt)||HiRec||85/100 Gold||4.5/5||5/5||4.5/5||2013||1,199||discont.||check|
|Sony A9 (⇒ lft)||HiRec||89/100 Gold||5/5||5/5||5/5||2017||4,499||latest||check|
|Canon 70D (⇒ lft | rgt)||HiRec||83/100 Gold||4.5/5||4.5/5||5/5||2013||1,199||discont.||check|
|Nikon D7500 (⇒ lft | rgt)||HiRec||86/100 Silver||5/5||4.5/5||4.5/5||2017||1,299||latest||check|
|Nikon D500 (⇒ lft | rgt)||HiRec||91/100 Gold||4.5/5||5/5||5/5||2016||1,999||latest||check|
|Nikon D7200 (⇒ lft | rgt)||HiRec||84/100 Silver||4.5/5||4/5||4.5/5||2015||1,199||discont.||check|
|Nikon D3300 (⇒ lft | rgt)||Rec||77/100 Silver||4.5/5||4.5/5||4.5/5||2014||499||discont.||check|
|Nikon D750 (⇒ lft | rgt)||HiRec||90/100 Gold||4.5/5||5/5||4.5/5||2014||2,299||latest||check|
|Nikon D610 (⇒ lft | rgt)||HiRec||87/100 Gold||4.5/5||4.5/5||4.5/5||2013||1,999||latest||check|
|Nikon D600 (⇒ lft | rgt)||HiRec||87/100 Gold||5/5||4.5/5||4.5/5||2012||2,099||discont.||check|
|Nikon D7000 (⇒ lft | rgt)||-||80/100 Silver||4.5/5||5/5||4.5/5||2010||1,499||discont.||check|
|Sony A7 III (⇒ lft | rgt)||HiRec||89/100 Gold||5/5||..||5/5||2018||1,999||latest||check|
|Sony A7R III (⇒ lft | rgt)||HiRec||90/100 Gold||4.5/5||5/5||5/5||2017||3,199||latest||check|
|Sony A7R II (⇒ lft | rgt)||HiRec||90/100 Gold||5/5||4.5/5||5/5||2015||3,199||discont.||check|
|Sony A7S II (⇒ lft | rgt)||Rec||-||4.5/5||5/5||5/5||2015||2,999||latest||check|
|Sony A7 II (⇒ lft | rgt)||Rec||82/100 Silver||4.5/5||5/5||5/5||2014||1,999||discont.||check|
|Sony RX10 (⇒ lft | rgt)||Rec||80/100 Gold||4.5/5||4.5/5||4.5/5||2013||1,299||discont.||check|
The above review scores should be interpreted with care, though. The ratings were established in reference to similarly priced cameras that were available in the market at the time of the review. Hence, a score should always be seen in the context of the camera's market launch date and its price, and comparisons of ratings among very different cameras or across long time periods 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 are interested in seeing how other cameras pair up, just make a corresponding selection in the search boxes below. There is also a set of direct links to comparison reviews that other users of the CAM-parator app explored. If you cannot find the camera you are interested in, please send me an email, and I will try to add information on that model to the database.
- Canon 1D vs Leica M10
- Canon 200D vs Sony RX10 IV
- Canon 5D Mark III vs Canon G5 X
- Fujifilm X-T20 vs Nikon D5600
- Fujifilm X10 vs Fujifilm X30
- Fujifilm X70 vs Canon G1 X Mark II
- Leica M Typ 240 vs Sony RX10 IV
- Leica M10 vs Canon T5
- Nikon D4S vs Nikon D3X
- Nikon D7500 vs Sony A7
- Pentax Q vs Sony A5100
- Sony A9 vs Fujifilm X-H1