PW

Sony A7S II versus Olympus E-M1 II

The Sony Alpha 7S II and the Olympus OM-D E-M1 Mark II are two digital cameras that were revealed to the public, respectively, in September 2015 and September 2016. Both the A7S II and the E-M1 II are mirrorless interchangeable lens cameras that are based on a full frame (A7S II) and a Four Thirds (E-M1 II) sensor. The Sony has a resolution of 12 megapixel, whereas the Olympus provides 20.2 MP. 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: Sony A7S II vs Olympus E-M1 II

The physical size and weight of the Sony A7S II and the Olympus E-M1 II 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 A7S II – represents 100 percent across all the size and weight measures).

Snapsort Sony A7S II vs Olympus E-M1 II
Compare A7S II versus E-M1 II top
Compare A7S II and E-M1 II rear

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony A7S II and the Olympus E-M1 IIare of equal size. However, the E-M1 II is markedly lighter (8 percent) than the A7S II. 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 Sony FE Lens Catalog (A7S II) and the Micro Four Thirds Lens Catalog (E-M1 II). 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 A7S II gets 370 shots out of its NP-FW50 battery, while the E-M1 II can take 440 images on a single charge of its BLH-1 power pack.

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
  Camera
Model
Camera
Width
Camera
Height
Camera
Depth
Camera
Weight
Battery
Life
(CIPA)
Weather
Sealing
(yes/no)
Camera
Launch
(announced)
Launch
Price
(USD)
Street
Price
(USD)
Used
Price
(USD)
Camera
Model
Sony A7S II» 5.0 in 3.8 in 2.4 in 22.1 oz 370 Y Sep 2015 2,999 i i Sony A7S II
Olympus E-M1 II« 5.3 in 3.6 in 2.6 in 20.2 oz 440 Y Sep 2016 1,999 i i Olympus E-M1 II
Olympus PEN-F« » 4.9 in 2.8 in 1.5 in 15.1 oz 330 n Jan 2016 1,199 i i Olympus PEN-F
Olympus E-M5 II« » 4.9 in 3.3 in 1.8 in 16.5 oz 310 Y Feb 2015 1,099 i i Olympus E-M5 II
Olympus E-M1« » 5.1 in 3.7 in 2.5 in 17.5 oz 350 Y Sep 2013 1,399- i Olympus E-M1
Panasonic GH5« » 5.5 in 3.9 in 3.4 in 25.6 oz 410 Y Jan 2017 1,999 i i Panasonic GH5
Panasonic G85« » 5.0 in 3.5 in 2.9 in 17.8 oz 330 Y Sep 2016 899 i i Panasonic G85
Sony A7 III« » 5.0 in 3.8 in 2.9 in 22.9 oz 610 Y Feb 2018 1,999 i i Sony A7 III
Sony A9« » 5.0 in 3.8 in 2.5 in 23.7 oz 650 Y Apr 2017 4,499 i i Sony A9
Sony A7R III« » 5.0 in 3.8 in 2.9 in 22.9 oz 650 Y Oct 2017 3,199 i i Sony A7R III
Sony A99 II« » 5.6 in 4.1 in 3.0 in 29.9 oz 490 Y Sep 2016 3,199 i i Sony A99 II
Sony A6500« » 4.7 in 2.6 in 2.1 in 16.0 oz 350 Y Oct 2016 1,399 i i Sony A6500
Sony A7R II« » 5.0 in 3.8 in 2.4 in 22.0 oz 290 Y Jun 2015 3,199- i Sony A7R II
Sony A7 II« » 5.0 in 3.8 in 2.4 in 21.1 oz 350 Y Nov 2014 1,999- i Sony A7 II
Sony A7S« » 5.0 in 3.7 in 1.9 in 17.2 oz 380 Y Apr 2014 2,499- i Sony A7S
Sony A99« » 5.8 in 4.4 in 3.1 in 28.6 oz 500 Y Sep 2012 2,799- i Sony A99

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 E-M1 II was launched at a markedly lower price (by 33 percent) than the A7S 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. Then, after the new model is out, very good deals can frequently be found on the pre-owned market.

 

Sensor comparison: Sony A7S II vs Olympus E-M1 II

The size of the imaging sensor is a crucial determinant 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. 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.

Of the two cameras under consideration, the Sony A7S II features a full frame sensor and the Olympus E-M1 II a Four Thirds sensor. The sensor area in the E-M1 II is 73 percent smaller. As a result of these sensor size differences, the cameras have a format factor of, respectively, 1.0 and 2.0. The sensor in the A7S II has a native 3:2 aspect ratio, while the one in the E-M1 II offers a 4:3 aspect.

Sony A7S II and Olympus E-M1 II sensor measures

Despite having a smaller sensor, the E-M1 II offers a higher resolution of 20.2 megapixel, compared with 12 MP of the A7S II. This megapixel advantage comes at the cost of a higher pixel density and a smaller size of the individual pixel (with a pixel pitch of 3.34μm versus 8.40μm for the A7S II). However, it should be noted that the E-M1 II is a somewhat more recent model (by 1 year) than the A7S II, and its sensor might have benefitted from technological advances during this time that partly offset its pixel-size disadvantage. Coming back to sensor resolution, it should be mentioned that the E-M1 II has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

Unlike the A7S II, the E-M1 II has the capacity to capture high quality composite images (50MP) by combining multiple shots after shifting its sensor by miniscule distances. This multi-shot, pixel-shift mode is most suitable for photography of stationary objects (landscapes, studio scenes).

A7S II versus E-M1 II MP

Since 2007, DXO Mark has published sensor performance measurements that have been derived using a consistent methodology. 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 review, the A7S II has a notably higher overall DXO score than the E-M1 II (overall score 5 points higher), which gives it an advantage in terms of imaging quality. This advantage is based on 0.099999999999998 bits lower color depth, 0.5 EV in additional dynamic range, and 1.2 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.

Sensor Characteristics
  Camera
Model
Sensor
Class
Resolution
(MP)
Horiz.
Pixels
Vert.
Pixels
Video
Format
DXO
Portrait
DXO
Landscape
DXO
Sports
DXO
Overall
Camera
Model
Sony A7S II» Full Frame 12.0 4240 28324K/30p23.613.3299385Sony A7S II
Olympus E-M1 II« Four Thirds 20.2 5184 38884K/30p23.712.8131280Olympus E-M1 II
Olympus PEN-F« » Four Thirds 20.2 5184 38881080/60p23.112.489474Olympus PEN-F
Olympus E-M5 II« » Four Thirds 15.9 4608 34561080/60p23.012.584273Olympus E-M5 II
Olympus E-M1« » Four Thirds 15.9 4608 34561080/30p23.012.775773Olympus E-M1
Panasonic GH5« » Four Thirds 20.2 5184 38884K/60p23.913.080777Panasonic GH5
Panasonic G85« » Four Thirds 15.8 4592 34484K/30p22.812.565671Panasonic G85
Sony A7 III« » Full Frame 24.0 6000 40004K/30p25.014.7373096Sony A7 III
Sony A9« » Full Frame 24.0 6000 40004K/30p24.913.3351792Sony A9
Sony A7R III« » Full Frame 42.2 7952 53044K/30p26.014.73523100Sony A7R III
Sony A99 II« » Full Frame 42.2 7952 53044K/30p25.413.4231792Sony A99 II
Sony A6500« » APS-C 24.0 6000 40004K/30p24.513.7140585Sony A6500
Sony A7R II« » Full Frame 42.2 7952 53044K/30p26.013.9343498Sony A7R II
Sony A7 II« » Full Frame 24.0 6000 40001080/60p24.913.6244990Sony A7 II
Sony A7S« » Full Frame 12.0 4240 28321080/60p23.913.2370287Sony A7S
Sony A99« » Full Frame 24.0 6000 40001080/60p25.014.0155589Sony A99

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, and both provide the same movie specifications (4K/30p).

 

Feature comparison: Sony A7S II vs Olympus E-M1 II

Beyond body and sensor, cameras can and do differ across a range of features. The two cameras under consideration are similar with respect to both having an electronic viewfinder. However, the one in the A7S II offers a slightly higher resolution than the one in the E-M1 II (2400k vs 2360k dots). The adjacent table lists some of the other core features of the Sony A7S II and Olympus E-M1 II along with similar information for a selection of comparators. If you need more detail on the specs, you can find comprehensive listings, for example, in the dpreview camera hub.

Core Features
  Camera
Model
Viewfinder
(Type or
'000 dots)
Control
Panel
(yes/no)
LCD
Size
(inch)
LCD
Resolution
('000 dots)
LCD
Attach-
ment
Touch
Screen
(yes/no)
Shutter
speed
(1/sec)
Shutter
flaps
(1/sec))
Build-in
Flash
(yes/no)
Build-in
Image
Stab
Camera
Model
Sony A7S II»2400 n 3.0 1229 tilting n 8000 5.0 n Y Sony A7S II
Olympus E-M1 II«2360 n 3.0 1037 swivel Y 8000 18.0 n Y Olympus E-M1 II
Olympus PEN-F« »2360 n 3.0 1037 swivel Y 8000 10.0 n Y Olympus PEN-F
Olympus E-M5 II« »2360 n 3.0 1037 swivel Y 8000 10.0 n Y Olympus E-M5 II
Olympus E-M1« »2360 n 3.0 1037 tilting Y 8000 10.0 n Y Olympus E-M1
Panasonic GH5« »3680 n 3.2 1620 swivel Y 8000 12.0 n Y Panasonic GH5
Panasonic G85« »2360 n 3.0 1040 swivel Y 4000 9.0 Y Y Panasonic G85
Sony A7 III« »2359 n 3.0 922 tilting Y 8000 10.0 n Y Sony A7 III
Sony A9« »3686 n 3.0 1440 tilting Y 8000 20.0 n Y Sony A9
Sony A7R III« »3686 n 3.0 1440 tilting Y 8000 10.0 n Y Sony A7R III
Sony A99 II« »2400 Y 3.0 1229 full-flex n 8000 12.0 n Y Sony A99 II
Sony A6500« »2300 n 3.0 922 tilting Y 4000 11.0 Y Y Sony A6500
Sony A7R II« »2400 n 3.0 1229 tilting n 8000 5.0 n Y Sony A7R II
Sony A7 II« »2400 n 3.0 1230 tilting n 8000 5.0 n Y Sony A7 II
Sony A7S« »2400 n 3.0 921 tilting n 8000 5.0 n n Sony A7S
Sony A99« »2359 Y 3.0 1229 full-flex n 8000 6.0 n Y Sony A99

Both the A7S II and the E-M1 II are current models that good online retailers will have in stock. You can check the latest prices, for example, at amazon. The A7S II replaced the earlier Sony A7S, while the E-M1 II followed on from the Olympus E-M1.

Review summary: Sony A7S II vs Olympus E-M1 II

So what conclusions can be drawn? Is there a clear favorite between the Sony A7S II and the Olympus E-M1 II? The listing below highlights the relative strengths of the two models.

ilogo

Arguments in favor of the Sony Alpha 7S II:

  • Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
  • Better image quality: Scores markedly higher (5 points) in the DXO overall assessment.
  • Better low-light sensitivity: Requires less light for good images (1.2 stops ISO advantage).
  • More detailed LCD: Has a higher resolution rear screen (1229k vs 1037k dots).
  • More heavily discounted: Has been on the market for longer (launched in September 2015).

ilogo

Advantages of the Olympus OM-D E-M1 Mark II:

  • More detail: Has more megapixels (20.2 vs 12MP), which boosts linear resolution by 27%.
  • Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
  • High quality composites: Can combine several shots after pixel-shifting its sensor.
  • More flexible LCD: Has swivel screen for odd-angle shots in portrait or landscape orientation.
  • Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
  • Faster burst: Shoots at higher frequency (18 vs 5 flaps/sec) to capture the decisive moment.
  • Longer lasting: Gets more shots (440 versus 370) out of a single battery charge.
  • More affordable: Was introduced into a lower priced category (33 percent cheaper at launch).
  • More modern: Was introduced somewhat (1 year) more recently.

If the count of relative strengths (bullet points above) is taken as a measure, the E-M1 II is the clear winner of the contest (9 : 5 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.

A7S II 05:09 E-M1 II

In any case, while the specs-based evaluation of cameras is instructive in revealing their potential as photographic tools, it says nothing about, for example, the handling, responsiveness, and overall imaging quality of the A7S II and the E-M1 II in practical situations. 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 summarizes the assessments of some of the best known camera review sites (cameralabs, dpreview, ephotozine, imaging-resource, photographyblog). The full reviews are available by clicking on the site logo in the table header.

Review Scores
  Camera
Model
cameralabs dpreview ephotozine imaging-resource photographyblog Camera
Launch
(announced)
Launch
Price
(USD)
Street
Price
(USD)
Used
Price
(USD)
Camera
Model
Sony A7S II»Rec-4.5/55/55/5 Sep 2015 2,999 i i Sony A7S II
Olympus E-M1 II«HiRec85/1004.5/55/54.5/5 Sep 2016 1,999 i i Olympus E-M1 II
Olympus PEN-F« »-82/1004.5/54.5/55/5 Jan 2016 1,199 i i Olympus PEN-F
Olympus E-M5 II« »HiRec81/1005/54.5/55/5 Feb 2015 1,099 i i Olympus E-M5 II
Olympus E-M1« »HiRec84/1004.5/54.5/54.5/5 Sep 2013 1,399- i Olympus E-M1
Panasonic GH5« »HiRec85/1004.5/55/55/5 Jan 2017 1,999 i i Panasonic GH5
Panasonic G85« »HiRec84/1005/54.5/54.5/5 Sep 2016 899 i i Panasonic G85
Sony A7 III« »HiRec89/1005/5-5/5 Feb 2018 1,999 i i Sony A7 III
Sony A9« »HiRec89/1005/55/55/5 Apr 2017 4,499 i i Sony A9
Sony A7R III« »HiRec90/1004.5/55/55/5 Oct 2017 3,199 i i Sony A7R III
Sony A99 II« »-85/1004.5/54.5/54.5/5 Sep 2016 3,199 i i Sony A99 II
Sony A6500« »HiRec85/1004.5/55/54.5/5 Oct 2016 1,399 i i Sony A6500
Sony A7R II« »HiRec90/1005/54.5/55/5 Jun 2015 3,199- i Sony A7R II
Sony A7 II« »Rec82/1004.5/55/55/5 Nov 2014 1,999- i Sony A7 II
Sony A7S« »-86/1004.5/54.5/55/5 Apr 2014 2,499- i Sony A7S
Sony A99« »-84/1004.5/5rev4.5/5 Sep 2012 2,799- i Sony A99

The review scores listed above should be treated with care, though. The ratings are only valid when refering to cameras in the same category and of the same age. Thus, a score needs to be put into the context of the launch date and the launch price of the camera, 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 would like to check on the differences and similarities of other camera models, just use the search menu below. An an alternative, you can also directly jump to any one of the listed comparisons that were previously generated by the CAM-parator tool. If the camera you are interested in is not available, kindly get in touch, and I will try to locate and add the respective data to the application.

vs

    You are here  »   »