Sony A77 vs A9
The Sony Alpha SLT-A77 and the Sony Alpha A9 are two digital cameras that were revealed to the public, respectively, in August 2011 and April 2017. The A77 is a DSLR, while the A9 is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (A77) and a full frame (A9) sensor. Both cameras offer a resolution of 24 megapixels.
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 SLT-A77 and the Sony Alpha A9? 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 side-by-side display below illustrates the physical size and weight of the Sony A77 and the Sony A9. The two cameras are presented according to their relative size. Three successive views from the front, the top, and the rear are shown. All size 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 A9 is notably smaller (18 percent) than the Sony A77. Moreover, the A9 is markedly lighter (8 percent) than the A77. 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 A77 gets 470 shots out of its NP-FM500H battery, while the A9 can take 650 images on a single charge of its NP-FZ100 power pack. The power pack in the A9 can be charged via the USB port, which can be very convenient 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, you can use the CAM-parator app to select your camera combination among a large number of options.
|Sony A77||143 mm||104 mm||81 mm||732 g||470||Y||Aug 2011||1,399|
|Sony A9||127 mm||96 mm||63 mm||673 g||650||Y||Apr 2017||4,499|
|Canon 6D||145 mm||111 mm||71 mm||770 g||1090||Y||Sep 2012||2,099|
|Nikon Z6||134 mm||101 mm||67 mm||675 g||310||Y||Aug 2018||1,999|
|Nikon D600||141 mm||113 mm||82 mm||850 g||900||Y||Sep 2012||2,099|
|Panasonic GH5||139 mm||98 mm||87 mm||725 g||410||Y||Jan 2017||1,999|
|Sony A9 II||129 mm||96 mm||76 mm||678 g||690||Y||Oct 2019||4,499|
|Sony A7 III||127 mm||96 mm||74 mm||650 g||610||Y||Feb 2018||1,999|
|Sony A7R III||127 mm||96 mm||74 mm||650 g||650||Y||Oct 2017||3,199|
|Sony A7 II||127 mm||96 mm||60 mm||599 g||350||Y||Nov 2014||1,999|
|Sony A77 II||143 mm||104 mm||81 mm||647 g||480||Y||May 2014||1,199|
|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.|
The price is, of course, an important factor in any camera decision. 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 A77 was launched at a markedly lower price (by 69 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.
The imaging sensor is at the core of digital cameras and its size is one of the main determining factors 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 are more costly to manufacture and tend to lead to bigger and heavier cameras and lenses.
Of the two cameras under consideration, the Sony A77 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 megapixels. 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 A77), which gives it a potential advantage in terms of light gathering capacity. In addition, the A9 is much more recent (by 5 years and 7 months) than the A77, and its sensor will have benefitted from technological advances during this time.
The A9 has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.
The Sony Alpha SLT-A77 has a native sensitivity range from ISO 100 to ISO 16000, which can be extended to ISO 50-25600. The corresponding ISO settings for the Sony Alpha A9 are ISO 100 to ISO 51200, with the possibility to increase the ISO range to 50-204800.
Consistent information on actual sensor performance is available from DXO Mark for many cameras. This service determines an overall sensor rating, as well as sub-scores for low-light sensitivity ("DXO Sports"), dynamic range ("DXO Landscape"), and color depth ("DXO Portrait"). Of the two cameras under consideration, the A9 offers substantially better image quality than the A77 (overall score 14 points higher). The advantage is based on 0.9 bits higher color depth, 0.1 EV in additional dynamic range, and 2.1 stops in additional low light sensitivity. The adjacent table reports on the physical sensor characteristics and the outcomes of the DXO sensor quality tests for a sample of comparator-cameras.
| DXO |
|Sony A9||Full Frame||24.0||6000||4000||4K/30p||24.9||13.3||3517||92|
|Canon 6D||Full Frame||20.0||5472||3648||1080/30p||23.8||12.1||2340||82|
|Nikon Z6||Full Frame||24.3||6048||4024||4K/30p||25.3||14.3||3299||95|
|Nikon D600||Full Frame||24.2||6016||4016||1080/30p||25.1||14.2||2980||94|
|Panasonic GH5||Four Thirds||20.2||5184||3888||4K/60p||23.9||13.0||807||77|
|Sony A9 II||Full Frame||24.0||6000||4000||4K/30p||25.0||14.0||3434||93|
|Sony A7 III||Full Frame||24.0||6000||4000||4K/30p||25.0||14.7||3730||96|
|Sony A7R III||Full Frame||42.2||7952||5304||4K/30p||26.0||14.7||3523||100|
|Sony A7 II||Full Frame||24.0||6000||4000||1080/60p||24.9||13.6||2449||90|
|Sony A77 II||APS-C||24.0||6000||4000||1080/60p||..||..||..||..|
|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. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, but the A9 provides a better video resolution than the A77. It can shoot movie footage at 4K/30p, while the A77 is limited to 1080/60p.
Apart from body and sensor, cameras can and do differ across a variety of features. The two cameras under review are similar with respect to both having an electronic viewfinder. However, the one in the A9 offers a substantially higher resolution than the one in the A77 (3686k vs 2359k dots). The adjacent table lists some of the other core features of the Sony A77 and Sony A9 along with similar information for a selection of comparators.
|Sony A9 II||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|Sony A7 III||2359||n||3.0||922||tilting||Y||1/8000s||10.0||n||Y|
|Sony A7R III||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|Sony A7 II||2400||n||3.0||1230||tilting||n||1/8000s||5.0||n||Y|
|Sony A77 II||2359||Y||3.0||1229||full-flex||n||1/8000s||12.0||Y||Y|
One difference between the cameras concerns the presence of an on-board flash. The A77 has one, while the A9 does not. While the built-in flash of the A77 is not very powerful, it can at times be useful as a fill-in light.The A77 has an articulated LCD that can be turned to be front-facing. This characteristic will be appreciated by vloggers and photographers who are interested in snapping selfies. In contrast, the A9 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 A9 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).
Concerning the storage of imaging data, both the A77 and the A9 write their files to SDXC or Memory Stick PRO Duo cards. The A9 features dual card slots, which can be very useful in case a memory card fails. In contrast, the A77 only has one slot. The A9 supports UHS-II cards (on its first slot), while the A77 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 SLT-A77 and Sony Alpha A9 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
| NFC |
|Sony A9 II||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|Sony A7 III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|Sony A7R III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|Sony A7 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
|Sony A77 II||Y||stereo||mono||Y||-||mini||2.0||Y||Y||-|
It is notable that the A9 offers wifi support, which can be a very convenient means to transfer image data to an off-camera location. In contrast, the A77 does not provide wifi capability.
Both cameras feature a PC Sync terminal to control professional strobe lights, which will be appreciated by studio photographers.
Travel and landscape photographers will find it useful that the A77 has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.
Both the A77 and the A9 have been discontinued, but can regularly be found used on eBay. The A77 was replaced by the Sony A77 II, while the A9 was followed by the Sony A9 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 conclusions can be drawn? Is the Sony A77 better than the Sony A9 or vice versa? The listing below highlights the relative strengths of the two models.
Advantages of the Sony Alpha SLT-A77:
- Easier setting verification: Features an LCD display on top to control shooting parameters.
- More flexible LCD: Has a full-flex screen for odd-angle shots in portrait or landscape orientation.
- More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
- Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
- Easier geotagging: Features an internal GPS sensor to log localization data.
- More affordable: Was introduced into a lower priced category (69 percent cheaper at launch).
- More heavily discounted: Has been available for much longer (launched in August 2011).
Arguments in favor of the Sony Alpha A9:
- Better image quality: Scores substantially higher (14 points) in the DXO overall evaluation.
- Better low-light sensitivity: Can shoot in dim conditions (2.1 stops ISO advantage).
- 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.
- Better sound control: Has a headphone port that enables audio monitoring while recording.
- More detailed viewfinder: Has higher resolution electronic viewfinder (3686k vs 2359k dots).
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.78x vs 0.73x).
- More detailed LCD: Has a higher resolution rear screen (1440k vs 921k dots).
- Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
- Faster burst: Shoots at higher frequency (20 vs 12 flaps/sec) to capture the decisive moment.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- More compact: Is smaller (127x96mm vs 143x104mm) and will fit more readily into a bag.
- Longer lasting: Gets more shots (650 versus 470) out of a single battery charge.
- Easier travel charging: Can be conveniently charged via its USB port.
- More legacy lens friendly: Can use many 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.
- 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 modern: Reflects 5 years and 7 months of technical progress since the A77 launch.
If the number of relative strengths (bullet points above) is taken as a guide, the A9 is the clear winner of the contest (21 : 7 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 A77 and the Sony A9 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 says little about, for example, the shooting experience and imaging performance of the A77 and the A9 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 A77||91/100||81/100||..||4.5/5||5/5||Aug 2011||1,399|
|Sony A9||+ +||89/100||5/5||5/5||5/5||Apr 2017||4,499|
|Canon 6D||+ +||83/100||4.5/5||4.5/5||4.5/5||Sep 2012||2,099|
|Nikon Z6||..||..||4.5/5||4.5/5||5/5||Aug 2018||1,999|
|Nikon D600||+ +||87/100||5/5||4.5/5||4.5/5||Sep 2012||2,099|
|Panasonic GH5||+ +||85/100||4.5/5||5/5||5/5||Jan 2017||1,999|
|Sony A9 II||..||90/100||5/5||..||5/5||Oct 2019||4,499|
|Sony A7 III||+ +||89/100||5/5||5/5||5/5||Feb 2018||1,999|
|Sony A7R III||+ +||90/100||4.5/5||5/5||5/5||Oct 2017||3,199|
|Sony A7 II||+||82/100||4.5/5||5/5||5/5||Nov 2014||1,999|
|Sony A77 II||..||80/100||4.5/5||4/5||5/5||May 2014||1,199|
|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.|
Care should be taken when interpreting the review scores above, though. The ratings were established in reference to similarly priced cameras that were available in the market at the time of the review. Thus, a score needs to be put into the context of the launch date and the launch price 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? If you would like to see a different side-by-side camera review, just use the search menu below. There is also a set of direct links to comparison reviews that other users of the CAM-parator app explored.
Specifications: Sony A77 vs Sony A9
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 A77||Sony A9|
|Camera Type||Digital single lens reflex||Mirrorless system camera|
|Camera Lens||Sony A mount lenses||Sony E mount lenses|
|Launch Date||August 2011||April 2017|
|Launch Price||USD 1,399||USD 4,499|
|Sensor Specs||Sony A77||Sony A9|
|Sensor Format||APS-C Sensor||Full Frame Sensor|
|Sensor Size||23.5 x 15.6 mm||35.6 x 23.8 mm|
|Sensor Area||366.6 mm2||847.28 mm2|
|Sensor Diagonal||28.2 mm||42.8 mm|
|Sensor Resolution||24 Megapixels||24 Megapixels|
|Image Resolution||6000 x 4000 pixels||6000 x 4000 pixels|
|Pixel Pitch||3.91 μm||5.94 μm|
|Pixel Density||6.55 MP/cm2||2.83 MP/cm2|
|Moiré control||Anti-Alias filter||Anti-Alias filter|
|Movie Capability||1080/60p Video||4K/30p Video|
|ISO Setting||100 - 16,000 ISO||100 - 51,200 ISO|
|ISO Boost||50 - 25,600 ISO||50 - 204,800 ISO|
|Image Processor||BIONZ X||BIONZ X|
|DXO Sensor Quality (score)||78||92|
|DXO Color Depth (bits)||24.0||24.9|
|DXO Dynamic Range (EV)||13.2||13.3|
|DXO Low Light (ISO)||801||3517|
|Screen Specs||Sony A77||Sony A9|
|Viewfinder Type||Electronic viewfinder||Electronic viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||2359k dots||3686k dots|
|Top-Level Screen||Control Panel||no Top Display|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.0inch||3.0inch|
|LCD Resolution||921k dots||1440k dots|
|LCD Attachment||Fully flexible screen||Tilting screen|
|Touch Input||no Touchscreen||Touchscreen|
|Shooting Specs||Sony A77||Sony A9|
|Focus System||Phase-detect AF||On-Sensor Phase-detect|
|Manual Focusing Aid||Focus Peaking||Focus Peaking|
|Max Shutter Speed (mechanical)||1/8000s||1/8000s|
|Continuous Shooting||12 shutter flaps/s||20 shutter flaps/s|
|Shutter Life Expectancy||150 000 actuations||500 000 actuations|
|Electronic Shutter||no E-Shutter||up to 1/32000s|
|Image Stabilization||In-body stabilization||In-body stabilization|
|Fill Flash||Build-in Flash||no On-Board Flash|
|Storage Medium||MS or SDXC cards||MS or SDXC cards|
|Second Storage Option||Single card slot||Dual card slots|
|UHS card support||UHS-I||Single UHS-II|
|Connectivity Specs||Sony A77||Sony A9|
|Studio Flash||PC Sync socket||PC Sync socket|
|USB Connector||USB 2.0||USB 2.0|
|HDMI Port||mini HDMI||micro HDMI|
|Microphone Port||External MIC port||External MIC port|
|Headphone Socket||no Headphone port||Headphone port|
|Wifi Support||no Wifi||Wifi built-in|
|Near-Field Communication||no NFC||NFC built-in|
|Bluetooth Support||no Bluetooth||Bluetooth built-in|
|Geotagging||GPS built-in||no internal GPS|
|Body Specs||Sony A77||Sony A9|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||470 shots per charge||650 shots per charge|
|In-Camera Charging||no USB charging||USB charging|
143 x 104 x 81 mm
(5.6 x 4.1 x 3.2 in)
127 x 96 x 63 mm
(5.0 x 3.8 x 2.5 in)
|Camera Weight||732 g (25.8 oz)||673 g (23.7 oz)|
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