Olympus E-M10 III vs Sony A77 II
The Olympus OM-D E-M10 Mark III and the Sony Alpha SLT-A77 II are two digital cameras that were revealed to the public, respectively, in August 2017 and May 2014. The E-M10 III is a mirrorless interchangeable lens camera, while the A77 II is a DSLR. The cameras are based on a Four Thirds (E-M10 III) and an APS-C (A77 II) sensor. The Olympus has a resolution of 15.9 megapixels, whereas the Sony provides 24 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 Olympus OM-D E-M10 Mark III and the Sony Alpha SLT-A77 II? 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 Olympus E-M10 III and the Sony A77 II 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 size dimensions are rounded to the nearest millimeter.
The E-M10 III can be obtained in two different colors (black, silver), while the A77 II is only available in black.
If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony A77 II is considerably larger (45 percent) than the Olympus E-M10 III. Moreover, the A77 II is substantially heavier (58 percent) than the E-M10 III. It is noteworthy in this context that the A77 II is splash and dust-proof, while the E-M10 III does not feature any corresponding weather-sealing.
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.
The adjacent table lists the principal physical characteristics of the two cameras alongside a wider set of alternatives. If you would like to visualize and compare a different camera combination, you can navigate to the CAM-parator app and make your selection from a broad list of cameras there.
|1.||Olympus E-M10 III||122 mm||84 mm||50 mm||410 g||330||n||Aug 2017||649|
|2.||Sony A77 II||143 mm||104 mm||81 mm||647 g||480||Y||May 2014||1,199|
|3.||Nikon D7200||136 mm||107 mm||76 mm||765 g||1110||Y||Mar 2015||1,199|
|4.||Nikon D7100||136 mm||107 mm||76 mm||765 g||950||Y||Feb 2013||1,199|
|5.||Olympus E-M10 IV||122 mm||84 mm||49 mm||383 g||360||n||Aug 2020||699|
|6.||Olympus E-PL10||117 mm||68 mm||39 mm||380 g||350||n||Oct 2019||599|
|7.||Olympus E-PL9||117 mm||68 mm||39 mm||380 g||350||n||Feb 2018||599|
|8.||Olympus E-PL8||115 mm||67 mm||38 mm||357 g||350||n||Sep 2016||549|
|9.||Olympus PEN-F||125 mm||72 mm||37 mm||427 g||330||n||Jan 2016||1,199|
|10.||Olympus E-M10 II||120 mm||83 mm||47 mm||390 g||320||n||Aug 2015||649|
|11.||Olympus E-M10||119 mm||82 mm||46 mm||396 g||320||n||Jan 2014||699|
|12.||Olympus E-PL7||115 mm||67 mm||38 mm||357 g||350||n||Aug 2014||599|
|13.||Olympus E-PL6||111 mm||64 mm||38 mm||325 g||360||n||May 2013||599|
|14.||Panasonic GX85||122 mm||71 mm||44 mm||426 g||290||n||Apr 2016||799|
|15.||Sony A68||143 mm||104 mm||81 mm||610 g||540||n||Nov 2015||699|
|16.||Sony A7 II||127 mm||96 mm||60 mm||599 g||350||Y||Nov 2014||1,999|
|17.||Sony A77||143 mm||104 mm||81 mm||732 g||470||Y||Aug 2011||1,399|
|Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.|
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 E-M10 III was launched at a markedly lower price (by 46 percent) than the A77 II, 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. Furthermore, a large sensor camera will give the photographer more possibilities to use shallow depth-of-field in order to 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 Olympus E-M10 III features a Four Thirds sensor and the Sony A77 II an APS-C sensor. The sensor area in the A77 II is 63 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 2.0 and 1.5. The sensor in the E-M10 III has a native 4:3 aspect ratio, while the one in the A77 II offers a 3:2 aspect.
With 24MP, the A77 II offers a higher resolution than the E-M10 III (15.9MP), but the A77 II nevertheless has larger individual pixels (pixel pitch of 3.91μm versus 3.76μm for the E-M10 III) due to its larger sensor. However, the E-M10 III is a much more recent model (by 3 years and 4 months) than the A77 II, and its sensor will have benefitted from technological advances during this time that enhance the light gathering capacity of its pixel-units. Coming back to sensor resolution, it should be mentioned that the E-M10 III has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.
The resolution advantage of the Sony A77 II implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the A77 II 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-M10 III are 23 x 17.3 inches or 58.5 x 43.9 cm for good quality, 18.4 x 13.8 inches or 46.8 x 35.1 cm for very good quality, and 15.4 x 11.5 inches or 39 x 29.3 cm for excellent quality prints.
The Olympus OM-D E-M10 Mark III has a native sensitivity range from ISO 200 to ISO 25600, which can be extended to ISO 100-25600. The corresponding ISO settings for the Sony Alpha SLT-A77 II are ISO 100 to ISO 25600, with the possibility to increase the ISO range to 50-51200.
Since 2007, DXO Mark has published sensor performance measurements that have been derived using a consistent methodology. 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 table below summarizes the physical sensor characteristics and sensor quality findings and compares them across a set of similar cameras.
| DXO |
|1.||Olympus E-M10 III||Four Thirds||15.9||4608||3456||4K/30p||..||..||..||..|
|2.||Sony A77 II||APS-C||24.0||6000||4000||1080/60p||..||..||..||..|
|5.||Olympus E-M10 IV||Four Thirds||20.2||5184||3888||4K/30p||..||..||..||..|
|6.||Olympus E-PL10||Four Thirds||15.9||4608||3456||4K/30p||..||..||..||..|
|7.||Olympus E-PL9||Four Thirds||15.9||4608||3456||4K/30p||..||..||..||..|
|8.||Olympus E-PL8||Four Thirds||15.9||4608||3456||1080/30p||..||..||..||..|
|9.||Olympus PEN-F||Four Thirds||20.2||5184||3888||1080/60p||23.1||12.4||894||74|
|10.||Olympus E-M10 II||Four Thirds||15.9||4608||3456||1080/60p||23.1||12.5||842||73|
|11.||Olympus E-M10||Four Thirds||15.9||4608||3456||1080/30p||22.8||12.3||884||72|
|12.||Olympus E-PL7||Four Thirds||15.9||4608||3456||1080/30p||22.7||12.4||873||72|
|13.||Olympus E-PL6||Four Thirds||15.9||4608||3456||1080/30p||..||..||..||..|
|14.||Panasonic GX85||Four Thirds||15.8||4592||3448||4K/30p||22.9||12.6||662||71|
|16.||Sony A7 II||Full Frame||24.0||6000||4000||1080/60p||24.9||13.6||2449||90|
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 E-M10 III provides a higher video resolution than the A77 II. It can shoot video footage at 4K/30p, while the Sony is limited to 1080/60p.
Apart from body and sensor, cameras can and do differ across a variety of features. The two cameras under consideration are similar with respect to both having an electronic viewfinder. However, the one in the E-M10 III offers a slightly higher resolution than the one in the A77 II (2360k vs 2359k dots). The adjacent table lists some of the other core features of the Olympus E-M10 III and Sony A77 II along with similar information for a selection of comparators.
|1.||Olympus E-M10 III||2360||n||3.0||1040||tilting||Y||1/4000s||8.6||Y||Y|
|2.||Sony A77 II||2359||Y||3.0||1229||full-flex||n||1/8000s||12.0||Y||Y|
|5.||Olympus E-M10 IV||2360||n||3.0||1040||tilting||Y||1/4000s||15.0||Y||Y|
|10.||Olympus E-M10 II||2360||n||3.0||1040||tilting||Y||1/4000s||8.0||Y||Y|
|16.||Sony A7 II||2400||n||3.0||1230||tilting||n||1/8000s||5.0||n||Y|
One differentiating feature between the two cameras concerns the touch sensitivity of the rear screen. The E-M10 III has a touchscreen, while the A77 II has a conventional panel. Touch control can be particularly helpful, for example, for setting the focus point.The A77 II 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 E-M10 III 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-M10 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 Olympus E-M10 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.
The E-M10 III writes its imaging data to SDXC cards, while the A77 II uses SDXC or Memory Stick PRO Duo cards. The E-M10 III supports UHS-II cards (Ultra High Speed data transfer of up to 312 MB/s), while the A77 II can use UHS-I cards (up to 104 MB/s).
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 Olympus OM-D E-M10 Mark III and Sony Alpha SLT-A77 II and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
| NFC |
|1.||Olympus E-M10 III||Y||stereo||mono||-||-||micro||2.0||Y||-||-|
|2.||Sony A77 II||Y||stereo||mono||Y||-||mini||2.0||Y||Y||-|
|5.||Olympus E-M10 IV||Y||stereo||mono||-||-||micro||2.0||Y||-||Y|
|10.||Olympus E-M10 II||Y||stereo||mono||-||-||micro||2.0||Y||-||-|
|16.||Sony A7 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
It is notable that the A77 II has a microphone port, which can help to improve the quality of audio recordings by attaching an external microphone. The E-M10 III does not feature such a mic input.
Studio photographers will appreciate that the Sony A77 II (unlike the E-M10 III) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
The A77 II is a recent model that features in the current product line-up of Sony. In contrast, the E-M10 III has been discontinued (but can be found pre-owned on eBay). As a replacement in the same line of cameras, the E-M10 III was succeeded by the Olympus E-M10 IV. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Olympus and Sony websites.
So how do things add up? Is there a clear favorite between the Olympus E-M10 III and the Sony A77 II? Which camera is better? A synthesis of the relative strong points of each of the models is listed below.
Arguments in favor of the Olympus OM-D E-M10 Mark III:
- Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
- Better video: Provides higher definition movie capture (4K/30p vs 1080/60p).
- Fewer buttons to press: Is equipped with a touch-sensitive rear screen to facilitate handling.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
- More compact: Is smaller (122x84mm vs 143x104mm) and thus needs less room in the bag.
- Less heavy: Is lighter (by 237g or 37 percent) and hence easier to carry around.
- More legacy lens friendly: Can take a broad range of non-native lenses via adapters.
- Faster buffer clearing: Supports a more advanced SD data transfer standard (UHS-II vs UHS-I).
- More affordable: Was introduced into a lower priced category (46 percent cheaper at launch).
- More modern: Reflects 3 years and 4 months of technical progress since the A77 II launch.
Advantages of the Sony Alpha SLT-A77 II:
- More detail: Has more megapixels (24 vs 15.9MP), which boosts linear resolution by 25%.
- Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
- Better sound: Can connect to an external microphone for higher quality sound recording.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.73x vs 0.62x).
- Easier setting verification: Features a control panel on top to check shooting parameters.
- More detailed LCD: Has a higher resolution rear screen (1229k vs 1040k dots).
- 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.
- Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
- Faster burst: Shoots at higher frequency (12 vs 8.6 flaps/sec) to capture the decisive moment.
- Longer lasting: Gets more shots (480 versus 330) out of a single battery charge.
- Better sealing: Is splash and dust sealed for shooting in inclement weather conditions.
- Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
- Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
- More heavily discounted: Has been around for much longer (launched in May 2014).
If the count of individual advantages (bullet points above) is taken as a guide, the A77 II is the clear winner of the contest (15 : 11 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 Olympus E-M10 III and the Sony A77 II 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 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 E-M10 III or the A77 II perform in practice. User reviews that are available, for instance, at amazon can sometimes shed light on these issues, but such feedback is all too often partial, inconsistent, and inaccurate.
This is why hands-on reviews by experts are important. The following table reports the overall ratings of the cameras as published by some of the major 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.||Olympus E-M10 III||..||+||80/100||4.5/5||4.5/5||Aug 2017||649|
|2.||Sony A77 II||4/5||..||80/100||4.5/5||5/5||May 2014||1,199|
|3.||Nikon D7200||4/5||+ +||84/100||4.5/5||4.5/5||Mar 2015||1,199|
|4.||Nikon D7100||5/5||+ +||85/100||4.5/5||4.5/5||Feb 2013||1,199|
|5.||Olympus E-M10 IV||4.5/5||..||..||4.5/5||4.5/5||Aug 2020||699|
|6.||Olympus E-PL10||..||..||77/100||..||4/5||Oct 2019||599|
|7.||Olympus E-PL9||..||+||..||4.5/5||4/5||Feb 2018||599|
|8.||Olympus E-PL8||..||..||..||4.5/5||4/5||Sep 2016||549|
|9.||Olympus PEN-F||..||..||82/100||4.5/5||5/5||Jan 2016||1,199|
|10.||Olympus E-M10 II||4.5/5||+ +||80/100||5/5||5/5||Aug 2015||649|
|11.||Olympus E-M10||4/5||..||80/100||5/5||5/5||Jan 2014||699|
|12.||Olympus E-PL7||4/5||+||..||5/5||4/5||Aug 2014||599|
|13.||Olympus E-PL6||..||..||..||..||..||May 2013||599|
|14.||Panasonic GX85||4.5/5||+ +||82/100||5/5||5/5||Apr 2016||799|
|15.||Sony A68||3/5||..||..||4/5||4/5||Nov 2015||699|
|16.||Sony A7 II||5/5||+||82/100||4.5/5||5/5||Nov 2014||1,999|
|17.||Sony A77||5/5||91/100||81/100||..||5/5||Aug 2011||1,399|
|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 comparing ratings of very distinct cameras or ones that are far apart in terms of their release date have little meaning. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.
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: Olympus E-M10 III vs Sony A77 II
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||Olympus E-M10 III||Sony A77 II|
|Camera Type||Mirrorless system camera||Digital single lens reflex|
|Camera Lens||Micro Four Thirds lenses||Sony A mount lenses|
|Launch Date||August 2017||May 2014|
|Launch Price||USD 649||USD 1,199|
|Sensor Specs||Olympus E-M10 III||Sony A77 II|
|Sensor Format||Four Thirds Sensor||APS-C Sensor|
|Sensor Size||17.3 x 13.0 mm||23.5 x 15.6 mm|
|Sensor Area||224.9 mm2||366.6 mm2|
|Sensor Diagonal||21.6 mm||28.2 mm|
|Sensor Resolution||15.9 Megapixels||24 Megapixels|
|Image Resolution||4608 x 3456 pixels||6000 x 4000 pixels|
|Pixel Pitch||3.76 μm||3.91 μm|
|Pixel Density||7.08 MP/cm2||6.55 MP/cm2|
|Moiré control||no AA filter||Anti-Alias filter|
|Movie Capability||4K/30p Video||1080/60p Video|
|ISO Setting||200 - 25,600 ISO||100 - 25,600 ISO|
|ISO Boost||100 - 25,600 ISO||50 - 51,200 ISO|
|Image Processor||TruePic VIII||BIONZ X|
|Screen Specs||Olympus E-M10 III||Sony A77 II|
|Viewfinder Type||Electronic viewfinder||Electronic viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||2360k dots||2359k dots|
|Top-Level Screen||no Top Display||Control Panel|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.0inch||3.0inch|
|LCD Resolution||1040k dots||1229k dots|
|LCD Attachment||Tilting screen||Fully flexible screen|
|Touch Input||Touchscreen||no Touchscreen|
|Shooting Specs||Olympus E-M10 III||Sony A77 II|
|Focus System||Contrast-detect AF||Phase-detect AF|
|Manual Focusing Aid||Focus Peaking||Focus Peaking|
|Max Shutter Speed (mechanical)||1/4000s||1/8000s|
|Continuous Shooting||8.6 shutter flaps/s||12 shutter flaps/s|
|Electronic Shutter||up to 1/16000s||no E-Shutter|
|Time-Lapse Photography||Intervalometer built-in||no Intervalometer|
|Image Stabilization||In-body stabilization||In-body stabilization|
|Fill Flash||Build-in Flash||Build-in Flash|
|Storage Medium||SDXC cards||MS or SDXC cards|
|Second Storage Option||Single card slot||Single card slot|
|UHS card support||UHS-II||UHS-I|
|Connectivity Specs||Olympus E-M10 III||Sony A77 II|
|Studio Flash||no PC Sync||PC Sync socket|
|USB Connector||USB 2.0||USB 2.0|
|HDMI Port||micro HDMI||mini HDMI|
|Microphone Port||no MIC socket||External MIC port|
|Wifi Support||Wifi built-in||Wifi built-in|
|Near-Field Communication||no NFC||NFC built-in|
|Body Specs||Olympus E-M10 III||Sony A77 II|
|Environmental Sealing||not weather sealed||Weathersealed body|
|Battery Life (CIPA)||330 shots per charge||480 shots per charge|
122 x 84 x 50 mm
(4.8 x 3.3 x 2.0 in)
143 x 104 x 81 mm
(5.6 x 4.1 x 3.2 in)
|Camera Weight||410 g (14.5 oz)||647 g (22.8 oz)|
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