Sony A7 III vs A7S
The Sony Alpha A7 III and the Sony Alpha A7S are two digital cameras that were revealed to the public, respectively, in February 2018 and April 2014. Both the A7 III and the A7S are mirrorless interchangeable lens cameras that are equipped with a full frame sensor. The A7 III has a resolution of 24 megapixels, whereas the A7S provides 12 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 Sony Alpha A7 III and the Sony Alpha A7S? 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.
An illustration of the physical size and weight of the Sony A7 III and the Sony A7S is provided 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.
If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony A7S is somewhat smaller (2 percent) than the Sony A7 III. Moreover, the A7S is markedly lighter (25 percent) than the A7 III. 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. 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 Sony FE Lens Catalog. Mirrorless cameras, such as the two under consideration, have the additional advantage of having a short flange to focal plane distance, which makes it possible to mount many lenses from other systems onto the camera via adapters.
Concerning battery life, the A7 III gets 610 shots out of its NP-FZ100 battery, while the A7S can take 380 images on a single charge of its NP-FW50 power pack. The battery packs of both cameras can be charged via USB, 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. If you want to switch the focus of the display and review another camera pair, you can move across to the CAM-parator tool and choose from the broad selection of possible camera comparisons there.
|1.||Sony A7 III||127 mm||96 mm||74 mm||650 g||610||Y||Feb 2018||1,999|
|2.||Sony A7S||127 mm||94 mm||48 mm||489 g||380||Y||Apr 2014||2,499|
|3.||Canon 6D Mark II||144 mm||111 mm||75 mm||765 g||1200||Y||Jun 2017||1,999|
|4.||Nikon Z6||134 mm||101 mm||67 mm||675 g||310||Y||Aug 2018||1,999|
|5.||Nikon Df||144 mm||110 mm||67 mm||760 g||1400||Y||Nov 2013||2,749|
|6.||Sony A7C||124 mm||71 mm||60 mm||509 g||740||Y||Sep 2020||1,799|
|7.||Sony A9 II||129 mm||96 mm||76 mm||678 g||690||Y||Oct 2019||4,499|
|8.||Sony A7R IV||129 mm||96 mm||78 mm||665 g||670||Y||Jul 2019||3,499|
|9.||Sony A7R III||127 mm||96 mm||74 mm||650 g||650||Y||Oct 2017||3,199|
|10.||Sony A9||127 mm||96 mm||63 mm||673 g||650||Y||Apr 2017||4,499|
|11.||Sony A7R II||127 mm||96 mm||60 mm||625 g||290||Y||Jun 2015||3,199|
|12.||Sony A7S II||127 mm||96 mm||60 mm||627 g||370||Y||Sep 2015||2,999|
|13.||Sony A7 II||127 mm||96 mm||60 mm||599 g||350||Y||Nov 2014||1,999|
|14.||Sony A7||127 mm||94 mm||48 mm||474 g||340||Y||Oct 2013||1,699|
|15.||Sony A7R||127 mm||94 mm||48 mm||465 g||340||Y||Oct 2013||2,299|
|Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.|
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 A7 III was launched at a somewhat lower price (by 20 percent) than the A7S, which makes it more attractive for photographers on a tight budget. Normally, street prices remain initially close to the MSRP, but after a couple of months, the first discounts appear. 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. All other things equal, a large sensor will have larger individual pixel-units that offer better low-light sensitivity, wider dynamic range, and richer color-depth than smaller pixels in a sensor of the same technological generation. Further, a large sensor camera will give the photographer additional creative options when using shallow depth-of-field to isolate a subject from its background. On the downside, larger sensors tend to be associated with larger, more expensive camera bodies and lenses.
Both cameras under consideration feature a full frame sensor, but their sensors differ slightly in size. The sensor area in the A7S is 1 percent bigger. They nevertheless have the same format factor of 1.0. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.
Despite having a slightly smaller sensor, the Sony A7 III offers a higher resolution of 24 megapixels, compared with 12 MP of the Sony A7S. 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 5.94μm versus 8.45μm for the A7S). However, it should be noted that the A7 III is much more recent (by 3 years and 10 months) than the A7S, and its sensor will have benefitted from technological advances during this time that make it possible to gather light more efficiently.
The resolution advantage of the Sony A7 III implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the A7 III 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 Sony A7S are 21.2 x 14.2 inches or 53.8 x 36 cm for good quality, 17 x 11.3 inches or 43.1 x 28.8 cm for very good quality, and 14.1 x 9.4 inches or 35.9 x 24 cm for excellent quality prints.
The A7 III has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.
The Sony Alpha A7 III has a native sensitivity range from ISO 100 to ISO 51200, which can be extended to ISO 50-204800. The corresponding ISO settings for the Sony Alpha A7S are ISO 100 to ISO 102400, with the possibility to increase the ISO range to 50-409600.
Consistent information on actual sensor performance is available from DXO Mark for many 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 review, the A7 III has a notably higher overall DXO score than the A7S (overall score 9 points higher), which gives it an advantage in terms of imaging quality. This advantage is based on 1.1 bits higher color depth, 1.5 EV in additional dynamic range, and 0 stops in additional low light sensitivity. The following table provides an overview of the physical sensor characteristics, as well as the sensor quality measurements for a selection of comparators.
| DXO |
|1.||Sony A7 III||Full Frame||24.0||6000||4000||4K/30p||25.0||14.7||3730||96|
|2.||Sony A7S||Full Frame||12.0||4240||2832||1080/60p||23.9||13.2||3702||87|
|3.||Canon 6D Mark II||Full Frame||26.0||6240||4160||1080/60p||24.4||11.9||2862||85|
|4.||Nikon Z6||Full Frame||24.3||6048||4024||4K/30p||25.3||14.3||3299||95|
|5.||Nikon Df||Full Frame||16.2||4928||3280||none||24.6||13.1||3279||89|
|6.||Sony A7C||Full Frame||24.0||6000||4000||4K/30p||25.0||14.7||3407||95|
|7.||Sony A9 II||Full Frame||24.0||6000||4000||4K/30p||25.0||14.0||3434||93|
|8.||Sony A7R IV||Full Frame||60.2||9504||6336||4K/30p||26.0||14.8||3344||99|
|9.||Sony A7R III||Full Frame||42.2||7952||5304||4K/30p||26.0||14.7||3523||100|
|10.||Sony A9||Full Frame||24.0||6000||4000||4K/30p||24.9||13.3||3517||92|
|11.||Sony A7R II||Full Frame||42.2||7952||5304||4K/30p||26.0||13.9||3434||98|
|12.||Sony A7S II||Full Frame||12.0||4240||2832||4K/30p||23.6||13.3||2993||85|
|13.||Sony A7 II||Full Frame||24.0||6000||4000||1080/60p||24.9||13.6||2449||90|
|14.||Sony A7||Full Frame||24.0||6000||4000||1080/60p||24.8||14.2||2248||90|
|15.||Sony A7R||Full Frame||36.2||7360||4912||1080/60p||25.6||14.1||2746||95|
Many modern cameras cannot only take still pictures, but also record videos. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, but the A7 III provides a higher video resolution than the A7S. It can shoot video footage at 4K/30p, while the A7S is limited to 1080/60p.
Apart from body and sensor, cameras can and do differ across a range of features. The two cameras under review are similar with respect to both having an electronic viewfinder. However, the one in the A7S offers a slightly higher resolution than the one in the A7 III (2400k vs 2359k dots). The following table reports on some other key feature differences and similarities of the Sony A7 III, the Sony A7S, and comparable cameras.
|1.||Sony A7 III||2359||n||3.0||922||tilting||Y||1/8000s||10.0||n||Y|
|3.||Canon 6D Mark II||optical||Y||3.0||1040||swivel||Y||1/4000s||6.5||n||n|
|7.||Sony A9 II||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|8.||Sony A7R IV||5760||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|9.||Sony A7R III||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|11.||Sony A7R II||2400||n||3.0||1229||tilting||n||1/8000s||5.0||n||Y|
|12.||Sony A7S II||2400||n||3.0||1229||tilting||n||1/8000s||5.0||n||Y|
|13.||Sony A7 II||2400||n||3.0||1230||tilting||n||1/8000s||5.0||n||Y|
One feature that differentiates the A7 III and the A7S is in-body image stabilization (IBIS). The A7 III reduces the risk of handshake-induced blur with all attached lenses, while the A7S offers no blur reduction with lenses that themselves do not provide optical image stabilization.
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, both cameras under consideration feature an 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 Sony A7 III 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 A7 III and the A7S write their files to SDXC or Memory Stick PRO Duo cards. The A7 III features dual card slots, which can be very useful in case a memory card fails. In contrast, the A7S only has one slot. The A7 III supports UHS-II cards (on its first slot), while the A7S 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 Sony Alpha A7 III and Sony Alpha A7S and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
| NFC |
|1.||Sony A7 III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|3.||Canon 6D Mark II||Y||stereo||mono||Y||-||mini||2.0||Y||Y||Y|
|7.||Sony A9 II||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|8.||Sony A7R IV||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|9.||Sony A7R III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|11.||Sony A7R II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
|12.||Sony A7S II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
|13.||Sony A7 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
The A7 III is a recent model that features in the current product line-up of Sony. In contrast, the A7S has been discontinued (but can be found pre-owned on eBay). As a replacement in the same line of cameras, the A7S was succeeded by the Sony A7S II. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Sony website.
So what is the bottom line? Is there a clear favorite between the Sony A7 III and the Sony A7S? Which camera is better? The listing below highlights the relative strengths of the two models.
Arguments in favor of the Sony Alpha A7 III:
- More detail: Offers more megapixels (24 vs 12MP) with a 41% higher linear resolution.
- Better image quality: Scores markedly higher (9 points) in the DXO overall assessment.
- Richer colors: Generates images with noticeably better colors (1.1 bits more color depth).
- More dynamic range: Captures a larger spectrum of light and dark details (1.5 EV of extra DR).
- 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.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.78x vs 0.71x).
- Fewer buttons to press: Is equipped with a touch-sensitive rear screen to facilitate handling.
- Faster burst: Shoots at higher frequency (10 vs 5 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 (610 versus 380) on a single battery charge.
- Sharper images: Has hand-shake reducing image stabilization built-in.
- Faster data transfer: Supports a more advanced USB protocol (3.1 vs 2.0).
- Easier wireless transfer: Supports Bluetooth for image sharing without cables.
- Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
- Faster buffer clearing: Supports a more advanced SD data transfer standard (UHS-II vs UHS-I).
- More affordable: Was introduced into a lower priced segment (20 percent cheaper at launch).
- More modern: Reflects 3 years and 10 months of technical progress since the A7S launch.
Reasons to prefer the Sony Alpha A7S:
- Less heavy: Has a lower weight (by 161g or 25 percent) and is thus easier to take along.
- More heavily discounted: Has been around for much longer (launched in April 2014).
If the count of individual advantages (bullet points above) is taken as a guide, the A7 III is the clear winner of the match-up (18 : 2 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 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.
How about other alternatives? Do the specifications of the Sony A7 III and the Sony A7S place the cameras among the top in their class? Find out in the latest Best Mirrorless Interchangeable Lens 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 remains incomplete and does no justice, for example, to the way the A7 III or the A7S perform in practice. 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 where reviews by experts come in. The table below provides a synthesis of the camera assessments of some of the best known photo-gear 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.||Sony A7 III||..||+ +||89/100||5/5||5/5||Feb 2018||1,999|
|2.||Sony A7S||4/5||..||86/100||4.5/5||5/5||Apr 2014||2,499|
|3.||Canon 6D Mark II||4/5||+||80/100||4.5/5||4/5||Jun 2017||1,999|
|4.||Nikon Z6||5/5||..||89/100||4.5/5||5/5||Aug 2018||1,999|
|5.||Nikon Df||4/5||..||81/100||4/5||4/5||Nov 2013||2,749|
|6.||Sony A7C||3.5/5||..||86/100||4/5||4/5||Sep 2020||1,799|
|7.||Sony A9 II||..||..||90/100||5/5||5/5||Oct 2019||4,499|
|8.||Sony A7R IV||5/5||+||91/100||4.5/5||5/5||Jul 2019||3,499|
|9.||Sony A7R III||..||+ +||90/100||4.5/5||5/5||Oct 2017||3,199|
|10.||Sony A9||5/5||+ +||89/100||5/5||5/5||Apr 2017||4,499|
|11.||Sony A7R II||5/5||+ +||90/100||5/5||5/5||Jun 2015||3,199|
|12.||Sony A7S II||5/5||+||..||4.5/5||5/5||Sep 2015||2,999|
|13.||Sony A7 II||5/5||+||82/100||4.5/5||5/5||Nov 2014||1,999|
|14.||Sony A7||5/5||+ +||80/100||5/5||5/5||Oct 2013||1,699|
|15.||Sony A7R||5/5||+ +||82/100||4.5/5||5/5||Oct 2013||2,299|
|Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.|
The review scores listed above should be treated 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 rating-comparisons among cameras that span long time periods or concern very differently equipped models make little sense. 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.
Specifications: Sony A7 III vs Sony A7S
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||Sony A7 III||Sony A7S|
|Camera Type||Mirrorless system camera||Mirrorless system camera|
|Camera Lens||Sony E mount lenses||Sony E mount lenses|
|Launch Date||February 2018||April 2014|
|Launch Price||USD 1,999||USD 2,499|
|Sensor Specs||Sony A7 III||Sony A7S|
|Sensor Format||Full Frame Sensor||Full Frame Sensor|
|Sensor Size||35.6 x 23.8 mm||35.8 x 23.9 mm|
|Sensor Area||847.28 mm2||855.62 mm2|
|Sensor Diagonal||42.8 mm||43 mm|
|Sensor Resolution||24 Megapixels||12 Megapixels|
|Image Resolution||6000 x 4000 pixels||4240 x 2832 pixels|
|Pixel Pitch||5.94 μm||8.45 μm|
|Pixel Density||2.83 MP/cm2||1.40 MP/cm2|
|Moiré control||Anti-Alias filter||Anti-Alias filter|
|Movie Capability||4K/30p Video||1080/60p Video|
|ISO Setting||100 - 51,200 ISO||100 - 102,400 ISO|
|ISO Boost||50 - 204,800 ISO||50 - 409,600 ISO|
|Image Processor||BIONZ X||BIONZ X|
|DXO Sensor Quality (score)||96||87|
|DXO Color Depth (bits)||25.0||23.9|
|DXO Dynamic Range (EV)||14.7||13.2|
|DXO Low Light (ISO)||3730||3702|
|Screen Specs||Sony A7 III||Sony A7S|
|Viewfinder Type||Electronic viewfinder||Electronic viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||2359k dots||2400k dots|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.0inch||3.0inch|
|LCD Resolution||922k dots||921k dots|
|LCD Attachment||Tilting screen||Tilting screen|
|Touch Input||Touchscreen||no Touchscreen|
|Shooting Specs||Sony A7 III||Sony A7S|
|Focus System||On-Sensor Phase-detect||Contrast-detect AF|
|Manual Focusing Aid||Focus Peaking||Focus Peaking|
|Max Shutter Speed (mechanical)||1/8000s||1/8000s|
|Continuous Shooting||10 shutter flaps/s||5 shutter flaps/s|
|Time-Lapse Photography||Intervalometer built-in||no Intervalometer|
|Image Stabilization||In-body stabilization||Lens stabilization only|
|Fill Flash||no On-Board Flash||no On-Board Flash|
|Storage Medium||MS or SDXC cards||MS or SDXC cards|
|Second Storage Option||Dual card slots||Single card slot|
|UHS card support||Single UHS-II||UHS-I|
|Connectivity Specs||Sony A7 III||Sony A7S|
|USB Connector||USB 3.1||USB 2.0|
|HDMI Port||micro HDMI||micro HDMI|
|Microphone Port||External MIC port||External MIC port|
|Headphone Socket||Headphone port||Headphone port|
|Wifi Support||Wifi built-in||Wifi built-in|
|Near-Field Communication||NFC built-in||NFC built-in|
|Bluetooth Support||Bluetooth built-in||no Bluetooth|
|Body Specs||Sony A7 III||Sony A7S|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||610 shots per charge||380 shots per charge|
|In-Camera Charging||USB charging||USB charging|
127 x 96 x 74 mm
(5.0 x 3.8 x 2.9 in)
127 x 94 x 48 mm
(5.0 x 3.7 x 1.9 in)
|Camera Weight||650 g (22.9 oz)||489 g (17.2 oz)|
Did you notice an error on this page? If so, please get in touch, so that we can correct the information.