Sony A7S vs A900
The Sony Alpha A7S and the Sony Alpha A900 are two professional cameras that were officially introduced, respectively, in April 2014 and September 2008. The A7S is a mirrorless interchangeable lens camera, while the A900 is a DSLR. Both cameras are equipped with a full frame sensor. The A7S has a resolution of 12 megapixels, whereas the A900 provides 24.4 MP.
Below is an overview of the main specs of the two cameras as a starting point for the comparison.
|Sony A7S||Sony A900|
|Mirrorless system camera||Digital single lens reflex|
|Sony E mount lenses||Sony A mount lenses|
|12 MP, Full Frame Sensor||24.4 MP, Full Frame Sensor|
|1080/60p Video||no Video|
|ISO 100-102,400 (50 - 409,600)||ISO 200-3,200 (100 - 6,400)|
|Electronic viewfinder (2400k dots)||Optical viewfinder|
|3.0 LCD, 921k dots||3.0 LCD, 922k dots|
|Tilting screen (no touchscreen)||Fixed screen (not touch-sensitive)|
|5 shutter flaps per second||5 shutter flaps per second|
|Lens stabilization only||In-body stabilization|
|Weathersealed body||Weathersealed body|
|380 shots per battery charge||880 shots per battery charge|
|127 x 94 x 48 mm, 489 g||156 x 117 x 82 mm, 895 g|
Going beyond this snapshot of core features and characteristics, what are the differences between the Sony Alpha A7S and the Sony Alpha A900? 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 Sony A7S and the Sony A900 are illustrated 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 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 Sony A900 is considerably larger (53 percent) than the Sony A7S. Moreover, the A900 is substantially heavier (83 percent) than the A7S. 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. Hence, you might want to study and compare the specifications of available lenses in order to get the full picture of the size and weight of the two camera systems.
Concerning battery life, the A7S gets 380 shots out of its NP-FW50 battery, while the A900 can take 880 images on a single charge of its NP-FM500H power pack. The power pack in the A7S can be charged via the USB port, so that it is not always necessary to take the battery charger along when travelling.
The following table provides a synthesis of the main physical specifications of the two cameras and other similar ones. In case you want to display and compare another camera duo, just click on the right or left arrow next to the camera that you would like to inspect. Alternatively, you can also use the CAM-parator to select your camera combination among a larger number of options.
|Sony A7S||127 mm||94 mm||48 mm||489 g||380||Y||Apr 2014||2,499|
|Sony A900||156 mm||117 mm||82 mm||895 g||880||Y||Sep 2008||2,999|
|Canon 5D Mark II||152 mm||114 mm||75 mm||850 g||850||Y||Sep 2008||3,499|
|Nikon D750||141 mm||113 mm||78 mm||750 g||1230||Y||Sep 2014||2,299|
|Nikon Df||144 mm||110 mm||67 mm||760 g||1400||Y||Nov 2013||2,749|
|Panasonic S1||149 mm||110 mm||97 mm||1017 g||400||Y||Feb 2019||2,499|
|Panasonic GH4||133 mm||93 mm||84 mm||560 g||500||Y||Feb 2014||1,499|
|Sony A99 II||143 mm||104 mm||76 mm||849 g||490||Y||Sep 2016||3,199|
|Sony A6300||120 mm||67 mm||49 mm||404 g||400||Y||Feb 2016||999|
|Sony A7R II||127 mm||96 mm||60 mm||625 g||290||Y||Jun 2015||3,199|
|Sony A7S II||127 mm||96 mm||60 mm||627 g||370||Y||Sep 2015||2,999|
|Sony A7 II||127 mm||96 mm||60 mm||599 g||350||Y||Nov 2014||1,999|
|Sony A7||127 mm||94 mm||48 mm||474 g||340||Y||Oct 2013||1,699|
|Sony A7R||127 mm||94 mm||48 mm||465 g||340||Y||Oct 2013||2,299|
|Sony RX1R||113 mm||65 mm||70 mm||482 g||270||n||Jun 2013||2,799|
|Sony A99||147 mm||111 mm||78 mm||812 g||500||Y||Sep 2012||2,799|
|Sony A850||156 mm||117 mm||82 mm||895 g||880||Y||Aug 2009||1,999|
Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.
(1) Number of images that can be taken on a full battery charge according to the CIPA-standard; (2) Official announcement.
Any camera decision will naturally be influenced heavily by the price. The listed launch prices provide an indication of the market segment that the manufacturer of the cameras have been targeting. The A7S was launched at a somewhat lower price (by 17 percent) than the A900, 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. Then, after the new model is out, very good deals can frequently be found on the pre-owned market.
The size of the sensor inside a digital camera is one of the key determinants 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. 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.
Both cameras under consideration feature a full frame sensor, but their sensors differ slightly in size. The sensor area in the A900 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.
With 24.4MP, the A900 offers a higher resolution than the A7S (12MP), but the A900 has smaller individual pixels (pixel pitch of 5.94μm versus 8.45μm for the A7S). Yet, the A7S is a much more recent model (by 5 years and 6 months) than the A900, and its sensor will have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixel-units.
The resolution advantage of the Sony A900 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the A900 for good quality output (200 dots per inch) amounts to 30.2 x 20.2 inches or 76.8 x 51.2 cm, for very good quality (250 dpi) 24.2 x 16.1 inches or 61.4 x 41 cm, and for excellent quality (300 dpi) 20.2 x 13.4 inches or 51.2 x 34.1 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 Sony Alpha A7S has a native sensitivity range from ISO 100 to ISO 102400, which can be extended to ISO 50-409600. The corresponding ISO settings for the Sony Alpha A900 are ISO 200 to ISO 3200, with the possibility to increase the ISO range to 100-6400.
For many cameras, data on sensor performance has been reported by DXO Mark. 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 A7S has a notably higher overall DXO score than the A900 (overall score 8 points higher), which gives it an advantage in terms of imaging quality. This advantage is based on 0.2 bits higher color depth, 0.9 EV in additional dynamic range, and 1.4 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.
|Sony A7S||Full Frame||12.0||4240||2832||1080/60p||23.9||13.2||3702||87|
|Sony A900||Full Frame||24.4||6048||4032||none||23.7||12.3||1431||79|
|Canon 5D Mark II||Full Frame||21.0||5616||3744||1080/30p||23.7||11.9||1815||79|
|Nikon D750||Full Frame||24.2||6016||4016||1080/60p||24.8||14.5||2956||93|
|Nikon Df||Full Frame||16.2||4928||3280||none||24.6||13.1||3279||89|
|Panasonic S1||Full Frame||24.0||6000||4000||4K/60p||25.2||14.5||3333||95|
|Panasonic GH4||Four Thirds||15.9||4608||3456||4K/30p||23.2||12.8||791||74|
|Sony A99 II||Full Frame||42.2||7952||5304||4K/30p||25.4||13.4||2317||92|
|Sony A7R II||Full Frame||42.2||7952||5304||4K/30p||26.0||13.9||3434||98|
|Sony A7S II||Full Frame||12.0||4240||2832||4K/30p||23.6||13.3||2993||85|
|Sony A7 II||Full Frame||24.0||6000||4000||1080/60p||24.9||13.6||2449||90|
|Sony A7||Full Frame||24.0||6000||4000||1080/60p||24.8||14.2||2248||90|
|Sony A7R||Full Frame||36.2||7360||4912||1080/60p||25.6||14.1||2746||95|
|Sony RX1R||Full Frame||24.0||6000||4000||1080/60p||25.0||13.6||2537||91|
|Sony A99||Full Frame||24.0||6000||4000||1080/60p||25.0||14.0||1555||89|
|Sony A850||Full Frame||24.4||6048||4032||none||23.8||12.2||1415||79|
Many modern cameras are not only capable of taking still images, but also of capturing video footage. The A7S indeed provides movie recording capabilities, while the A900 does not. The highest resolution format that the A7S can use is 1080/60p.
Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A7S has an electronic viewfinder (2400k dots), while the A900 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 A900 has a higher magnification than the one of the A7S (0.74x vs 0.71x), 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 Sony A7S and Sony A900 in connection with corresponding information for a sample of similar cameras.
|Canon 5D Mark II||optical||Y||3.0||920||fixed||n||1/8000s||3.9||n||n|
|Sony A99 II||2400||Y||3.0||1229||full-flex||n||1/8000s||12.0||n||Y|
|Sony A7R II||2400||n||3.0||1229||tilting||n||1/8000s||5.0||n||Y|
|Sony A7S II||2400||n||3.0||1229||tilting||n||1/8000s||5.0||n||Y|
|Sony A7 II||2400||n||3.0||1230||tilting||n||1/8000s||5.0||n||Y|
One feature that differentiates the A900 and the A7S is in-body image stabilization (IBIS). The A900 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, the A7S 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 A7S writes its imaging data to SDXC or Memory Stick PRO Duo cards, while the A900 uses Compact Flash or Memory Stick PRO Duo cards. The A900 features dual card slots, which can be very useful in case a memory card fails. In contrast, the A7S only has one slot.
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 A7S and Sony Alpha A900 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
|Canon 5D Mark II||Y||mono||mono||Y||-||mini||2.0||-||-||-|
|Sony A99 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||Y|
|Sony A7R II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
|Sony A7S II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
|Sony A7 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
It is notable that the A7S offers wifi support, while the A900 does not. Wifi can be a very convenient means to transfer image data to an off-camera location.
Studio photographers will appreciate that the Sony A900 (unlike the A7S) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
Both the A7S and the A900 have been discontinued, but can regularly be found used on eBay. The A900 was replaced by the Sony A99, while the A7S was followed 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? Which of the two cameras – the Sony A7S or the Sony A900 – has the upper hand? Is one clearly better than the other? A synthesis of the relative strong points of each of the models is listed below.
Arguments in favor of the Sony Alpha A7S:
- Better image quality: Scores markedly higher (8 points) in the DXO overall assessment.
- More dynamic range: Captures a larger spectrum of light and dark details (0.9 EV of extra DR).
- Better low-light sensitivity: Requires less light for good images (1.4 stops ISO advantage).
- Broader imaging potential: Can record not only still images but also 1080/60p movies.
- More framing info: Has an electronic viewfinder that displays shooting data.
- More flexible LCD: Has a tilting screen for odd-angle shots in landscape orientation.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- More compact: Is smaller (127x94mm vs 156x117mm) and thus needs less room in the bag.
- Less heavy: Is lighter (by 406g or 45 percent) and hence easier to carry around.
- Easier travel charging: Can be conveniently charged via its USB port.
- More legacy lens friendly: Can take a broad range of non-native lenses via adapters.
- Easier file upload: Has wifi built in for automatic backup or image transfer to the web.
- Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
- More affordable: Was introduced into a lower priced segment (17 percent cheaper at launch).
- More modern: Reflects 5 years and 6 months of technical progress since the A900 launch.
Advantages of the Sony Alpha A900:
- More detail: Has more megapixels (24.4 vs 12MP), which boosts linear resolution by 43%.
- Brighter framing: Features an optical viewfinder for clear, lag-free composition.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.74x vs 0.71x).
- Easier setting verification: Features a control panel on top to check shooting parameters.
- Longer lasting: Gets more shots (880 versus 380) out of a single battery charge.
- Sharper images: Has stabilization technology built-in to reduce the impact of hand-shake.
- Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
- Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
- More heavily discounted: Has been around for much longer (launched in September 2008).
If the count of relative strengths (bullet points above) is taken as a measure, the A7S is the clear winner of the match-up (14 : 9 points). However, the pertinence of the various camera strengths will differ across photographers, so that you might want to weigh individual camera traits according to their importance for your own imaging needs before making a camera decision. 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 Sony A7S and the Sony A900 place the cameras among the top in their class? Find out in the latest Best Mirrorless Interchangeable Lens Camera and Best DSLR 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 says little about, for example, the shooting experience and imaging performance of the A7S and the A900 in practical situations. 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 table below provides a synthesis of the camera assessments of some of the best known photo-gear review sites (cameralabs, dpreview, ephotozine, imaging-resource, and photographyblog). 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.
|Sony A7S||..||86/100||4.5/5||4.5/5||5/5||Apr 2014||2,499|
|Sony A900||+ +||+ +||4.5/5||4/5||5/5||Sep 2008||2,999|
|Canon 5D Mark II||91/100||79/100||4/5||5/5||..||Sep 2008||3,499|
|Nikon D750||+ +||90/100||4.5/5||5/5||4.5/5||Sep 2014||2,299|
|Nikon Df||..||81/100||4/5||4/5||4/5||Nov 2013||2,749|
|Panasonic S1||+ +||88/100||4.5/5||..||4/5||Feb 2019||2,499|
|Panasonic GH4||+ +||85/100||5/5||5/5||5/5||Feb 2014||1,499|
|Sony A99 II||..||85/100||4.5/5||4.5/5||4.5/5||Sep 2016||3,199|
|Sony A6300||+||85/100||5/5||5/5||5/5||Feb 2016||999|
|Sony A7R II||+ +||90/100||5/5||4.5/5||5/5||Jun 2015||3,199|
|Sony A7S II||+||..||4.5/5||5/5||5/5||Sep 2015||2,999|
|Sony A7 II||+||82/100||4.5/5||5/5||5/5||Nov 2014||1,999|
|Sony A7||+ +||80/100||5/5||4.5/5||5/5||Oct 2013||1,699|
|Sony A7R||+ +||82/100||4.5/5||5/5||5/5||Oct 2013||2,299|
|Sony RX1R||..||..||4/5||o||4.5/5||Jun 2013||2,799|
|Sony A99||..||84/100||4.5/5||o||4.5/5||Sep 2012||2,799|
|Sony A850||..||75/100||..||4/5||4.5/5||Aug 2009||1,999|
|Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.|
The above review scores should be interpreted with care, though. The ratings are only valid when referring to cameras in the same category and of the same age. 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 your choice using the following search menu. As an alternative, you can also directly jump to any one of the listed comparisons that were previously generated by the CAM-parator tool.
Specifications: Sony A7S vs Sony A900
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 A7S||Sony A900|
|Camera Type||Mirrorless system camera||Digital single lens reflex|
|Camera Lens||Sony E mount lenses||Sony A mount lenses|
|Launch Date||April 2014||September 2008|
|Launch Price||USD 2,499||USD 2,999|
|Sensor Specs||Sony A7S||Sony A900|
|Sensor Format||Full Frame Sensor||Full Frame Sensor|
|Sensor Size||35.8 x 23.9 mm||35.9 x 24.0 mm|
|Sensor Area||855.62 mm2||861.6 mm2|
|Sensor Diagonal||43 mm||43.2 mm|
|Sensor Resolution||12 Megapixels||24.4 Megapixels|
|Image Resolution||4240 x 2832 pixels||6048 x 4032 pixels|
|Pixel Pitch||8.45 μm||5.94 μm|
|Pixel Density||1.40 MP/cm2||2.83 MP/cm2|
|Moiré control||Anti-Alias filter||Anti-Alias filter|
|Movie Capability||1080/60p Video||no Video|
|ISO Setting||100 - 102,400 ISO||200 - 3,200 ISO|
|ISO Boost||50 - 409,600 ISO||100 - 6,400 ISO|
|Image Processor||BIONZ X||BIONZ|
|DXO Sensor Quality (score)||87||79|
|DXO Color Depth (bits)||23.9||23.7|
|DXO Dynamic Range (EV)||13.2||12.3|
|DXO Low Light (ISO)||3702||1431|
|Screen Specs||Sony A7S||Sony A900|
|Viewfinder Type||Electronic viewfinder||Optical viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||2400k dots|
|Top-Level Screen||no Top Display||Control Panel|
|LCD Framing||Live View|
|Rear LCD Size||3.0inch||3.0inch|
|LCD Resolution||921k dots||922k dots|
|LCD Attachment||Tilting screen||Fixed screen|
|Shooting Specs||Sony A7S||Sony A900|
|Focus System||Contrast-detect AF||Phase-detect AF|
|Manual Focusing Aid||Focus Peaking||no Peaking Feature|
|Continuous Shooting||5 shutter flaps/s||5 shutter flaps/s|
|Electronic Shutter||YES||no E-Shutter|
|Image Stabilization||Lens stabilization only||In-body stabilization|
|Fill Flash||no On-Board Flash||no On-Board Flash|
|Storage Medium||MS or SDXC cards||CF or MS cards|
|Second Storage Option||Single card slot||Dual card slots|
|Connectivity Specs||Sony A7S||Sony A900|
|Studio Flash||no PC Sync||PC Sync socket|
|USB Connector||USB 2.0||USB 2.0|
|HDMI Port||micro HDMI||mini HDMI|
|Microphone Port||External MIC port||no MIC socket|
|Headphone Socket||Headphone port||no Headphone port|
|Wifi Support||Wifi built-in||no Wifi|
|Near-Field Communication||NFC built-in||no NFC|
|Body Specs||Sony A7S||Sony A900|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||380 shots per charge||880 shots per charge|
|In-Camera Charging||USB charging||no USB charging|
127 x 94 x 48 mm
(5.0 x 3.7 x 1.9 in)
156 x 117 x 82 mm
(6.1 x 4.6 x 3.2 in)
|Camera Weight||489 g (17.2 oz)||895 g (31.6 oz)|
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