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Pentax K-3 III vs Sony A7S

The Pentax K-3 III and the Sony Alpha A7S are two digital cameras that were revealed to the public, respectively, in March 2021 and April 2014. The K-3 III is a DSLR, while the A7S is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (K-3 III) and a full frame (A7S) sensor. The Pentax has a resolution of 25.6 megapixels, whereas the Sony provides 12 MP.

Below is an overview of the main specs of the two cameras as a starting point for the comparison.

Headline Specifications
Pentax K-3 III
versus
Sony A7S
Pentax K-3 III   Sony A7S
Digital single lens reflex Mirrorless system camera
Pentax K mount lenses Sony E mount lenses
25.6 MP, APS-C Sensor 12 MP, Full Frame Sensor
4K/30p Video 1080/60p Video
ISO 100-160,000 ISO 100-102,400 (50 - 409,600)
Optical viewfinder Electronic viewfinder (2400k dots)
3.2 LCD, 1620k dots 3.0 LCD, 921k dots
Fixed touchscreen Tilting screen (not touch-sensitive)
12 shutter flaps per second 5 shutter flaps per second
In-body stabilizationLens stabilization only
Weathersealed bodyWeathersealed body
800 shots per battery charge380 shots per battery charge
135 x 104 x 74 mm, 820 g 127 x 94 x 48 mm, 489 g

Going beyond this snapshot of core features and characteristics, what are the differences between the Pentax K-3 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.

Body comparison

The physical size and weight of the Pentax K-3 III and the Sony A7S 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 width, height and depth dimensions are rounded to the nearest millimeter.

The K-3 III can be obtained in two different colors (black, silver), while the A7S is only available in black.

Size Pentax K-3 III vs Sony A7S
Compare K-3 III versus A7S top
Comparison K-3 III or A7S rear

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony A7S is notably smaller (15 percent) than the Pentax K-3 III. Moreover, the A7S is substantially lighter (40 percent) than the K-3 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. 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 K-3 III gets 800 shots out of its D-LI90 battery, while the A7S can take 380 images on a single charge of its NP-FW50 power pack. The power pack in the A7S 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. 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.

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Body Specifications
    Camera
Model
Camera
Width
Camera
Height
Camera
Depth
Camera
Weight
Battery
Life
Weather
Sealing
Camera
Launch
Launch
Price (USD)
Street
Price
1.
 
Pentax K-3 III 135 mm 104 mm 74 mm 820 g 800 Y Mar 2021 1,999 i
2.
 
Sony A7S 127 mm 94 mm 48 mm 489 g 380 Y Apr 2014 2,499i
3.
 
Fujifilm X-T4 135 mm 93 mm 64 mm 607 g 500 Y Feb 2020 1,699 i
4.
 
Fujifilm X-H1 140 mm 97 mm 86 mm 673 g 310 Y Feb 2018 1,899 i
5.
 
Nikon D780 144 mm 116 mm 76 mm 840 g 2260 Y Jan 2020 2,299 i
6.
 
Nikon Z6 II 134 mm 101 mm 70 mm 705 g 410 Y Oct 2020 1,999 i
7.
 
Nikon Z6 134 mm 101 mm 67 mm 675 g 310 Y Aug 2018 1,999i
8.
 
Nikon D750 141 mm 113 mm 78 mm 750 g 1230 Y Sep 2014 2,299i
9.
 
Panasonic S5 133 mm 98 mm 82 mm 714 g 440 Y Sep 2020 1,999 i
10.
 
Pentax KP 132 mm 101 mm 76 mm 703 g 390 Y Jan 2017 1,099 i
11.
 
Pentax K-70 126 mm 93 mm 74 mm 688 g 410 Y Jun 2016 649 i
12.
 
Pentax K-3 II 131 mm 100 mm 77 mm 800 g 720 Y Apr 2015 1,099i
13.
 
Pentax K-3 131 mm 100 mm 77 mm 800 g 560 Y Oct 2013 1,299i
14.
 
Sony A7S II 127 mm 96 mm 60 mm 627 g 370 Y Sep 2015 2,999i
15.
 
Sony A7 127 mm 94 mm 48 mm 474 g 340 Y Oct 2013 1,699i
16.
 
Sony A7R 127 mm 94 mm 48 mm 465 g 340 Y Oct 2013 2,299i
17.
 
Sony RX1R 113 mm 65 mm 70 mm 482 g 270 n Jun 2013 2,799i
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 K-3 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. 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.

Sensor comparison

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. 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 are more costly to manufacture and tend to lead to bigger and heavier cameras and lenses.

Of the two cameras under consideration, the Pentax K-3 III features an APS-C sensor and the Sony A7S a full frame sensor. The sensor area in the A7S is 137 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.

Technology-wise, both cameras are equipped with CMOS (Complementary Metal–Oxide–Semiconductor) sensors.

Pentax K-3 III and Sony A7S sensor measures

Despite having a smaller sensor, the Pentax K-3 III offers a higher resolution of 25.6 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 3.76μm versus 8.45μm for the A7S). However, it should be noted that the K-3 III is much more recent (by 6 years and 11 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. Coming back to sensor resolution, it should be mentioned that the K-3 III has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The resolution advantage of the Pentax K-3 III implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the K-3 III for good quality output (200 dots per inch) amounts to 31 x 20.6 inches or 78.6 x 52.4 cm, for very good quality (250 dpi) 24.8 x 16.5 inches or 62.9 x 41.9 cm, and for excellent quality (300 dpi) 20.6 x 13.8 inches or 52.4 x 35 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.

Unlike the A7S, the K-3 III has the capacity to capture high quality composite images (YESMP) 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).

The Pentax K-3 III has a native sensitivity range from ISO 100 to ISO 160000. 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.

K-3 III versus A7S MP

Consistent information on actual sensor performance is available from DXO Mark for many cameras. 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 adjacent table reports on the physical sensor characteristics and the outcomes of the DXO sensor quality tests for a sample of comparator-cameras.

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Sensor Characteristics
    Camera
Model
Sensor
Class
Resolution
(MP)
Horiz.
Pixels
Vert.
Pixels
Video
Format
DXO
Portrait
DXO
Landscape
DXO
Sports
DXO
Overall
1.
 
Pentax K-3 III APS-C 25.6 6192 41284K/30p24.213.7208385
2.
 
Sony A7S Full Frame 12.0 4240 28321080/60p23.913.2370287
3.
 
Fujifilm X-T4 APS-C 26.0 6240 41604K/60p24.113.6199584
4.
 
Fujifilm X-H1 APS-C 24.0 6000 40004K/30p24.013.3180682
5.
 
Nikon D780 Full Frame 24.3 6048 40244K/30p25.314.3287795
6.
 
Nikon Z6 II Full Frame 24.3 6048 40244K/60p25.014.4330394
7.
 
Nikon Z6 Full Frame 24.3 6048 40244K/30p25.314.3329995
8.
 
Nikon D750 Full Frame 24.2 6016 40161080/60p24.814.5295693
9.
 
Panasonic S5 Full Frame 24.0 6000 40004K/60p25.114.5269794
10.
 
Pentax KP APS-C 24.1 6016 40001080/60i23.913.2169981
11.
 
Pentax K-70 APS-C 24.0 6000 40001080/60i23.813.1163980
12.
 
Pentax K-3 II APS-C 24.1 6016 40001080/60i23.613.6110680
13.
 
Pentax K-3 APS-C 24.1 6016 40001080/60i23.713.4121680
14.
 
Sony A7S II Full Frame 12.0 4240 28324K/30p23.613.3299385
15.
 
Sony A7 Full Frame 24.0 6000 40001080/60p24.814.2224890
16.
 
Sony A7R Full Frame 36.2 7360 49121080/60p25.614.1274695
17.
 
Sony RX1R Full Frame 24.0 6000 40001080/60p25.013.6253791
Note: DXO values in italics represent estimates based on sensor size and age.

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 K-3 III provides a higher video resolution than the A7S. It can shoot video footage at 4K/30p, while the Sony is limited to 1080/60p.

Feature comparison

Beyond body and sensor, cameras can and do differ across a range of features. For example, the A7S has an electronic viewfinder (2400k dots), while the K-3 III 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 A7S has a higher magnification than the one of the K-3 III (0.71x vs 0.70x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The adjacent table lists some of the other core features of the Pentax K-3 III and Sony A7S along with similar information for a selection of comparators.

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Core Features
    Camera
Model
Viewfinder
(Type or
000 dots)
Control
Panel
(yes/no)
LCD
Specifications
(inch/000 dots)
LCD
Attach-
ment
Touch
Screen
(yes/no)
Mech
Shutter
Speed
Shutter
Flaps
(1/sec)
Built-in
Flash
(yes/no)
Built-in
Image
Stab
1.
 
Pentax K-3 IIIoptical Y3.2 / 1620 fixed Y 1/8000s 12.0 n Y
2.
 
Sony A7S2400 n3.0 / 921 tilting n 1/8000s 5.0 n n
3.
 
Fujifilm X-T43690 n3.0 / 1620 swivel Y 1/8000s 15.0 n Y
4.
 
Fujifilm X-H13690 Y3.0 / 1040 full-flex Y 1/8000s 14.0 n Y
5.
 
Nikon D780optical Y3.2 / 2359 tilting Y 1/8000s 12.0 n n
6.
 
Nikon Z6 II3690 Y3.2 / 2100 tilting Y 1/8000s 14.0 n Y
7.
 
Nikon Z63690 Y3.2 / 2100 tilting Y 1/8000s 12.0 n Y
8.
 
Nikon D750optical Y3.2 / 1229 tilting n 1/4000s 6.0 Y n
9.
 
Panasonic S52360 n3.0 / 1840 swivel Y 1/8000s 7.0 n Y
10.
 
Pentax KPoptical n3.0 / 921 tilting n 1/6000s 7.0 Y Y
11.
 
Pentax K-70optical n3.0 / 921 swivel n 1/6000s 6.0 Y Y
12.
 
Pentax K-3 IIoptical Y3.2 / 1037 fixed n 1/8000s 8.3 n Y
13.
 
Pentax K-3optical Y3.2 / 1037 fixed n 1/8000s 8.3 Y Y
14.
 
Sony A7S II2400 n3.0 / 1229 tilting n 1/8000s 5.0 n Y
15.
 
Sony A72400 n3.0 / 1230 tilting n 1/8000s 5.0 n n
16.
 
Sony A7R2400 n3.0 / 1230 tilting n 1/8000s 4.0 n n
17.
 
Sony RX1Roptional n3.0 / 1229 fixed n 1/4000s 5.0 Y n

One feature that is present on the K-3 III, but is missing on the A7S is a top-level LCD. While being, of course, smaller than the rear screen, the control panel conveys some of the essential shooting information and can be convenient for quick and easy settings verification.

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 Pentax K-3 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 K-3 III writes its imaging data to SDXC cards, while the A7S uses SDXC or Memory Stick PRO Duo cards. The K-3 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 K-3 III supports UHS-II cards (on its first slot), while the A7S can use UHS-I cards.

Connectivity comparison

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 Pentax K-3 III and Sony Alpha A7S and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

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Input-Output Connections
    Camera
Model
Hotshoe
Port
Internal
Mic / Speaker
Microphone
Port
Headphone
Port
HDMI
Port
USB
Port
WiFi
Support
NFC
Support
Bluetooth
Support
1.
 
Pentax K-3 IIIYstereo / monoYYmicro3.2Y-Y
2.
 
Sony A7SYstereo / monoYYmicro2.0YY-
3.
 
Fujifilm X-T4Ystereo / monoY-micro3.1Y-Y
4.
 
Fujifilm X-H1Ystereo / monoY-micro3.0Y--
5.
 
Nikon D780Ystereo / monoYYmini3.1Y-Y
6.
 
Nikon Z6 IIYstereo / monoYYmicro3.2Y-Y
7.
 
Nikon Z6Ystereo / monoYYmicro3.1Y-Y
8.
 
Nikon D750Ystereo / monoYYmini2.0Y--
9.
 
Panasonic S5Ystereo / monoYYmicro3.2Y-Y
10.
 
Pentax KPYstereo / monoY--2.0Y--
11.
 
Pentax K-70Ystereo / monoY-mini2.0Y--
12.
 
Pentax K-3 IIYmono / monoYYmini3.0---
13.
 
Pentax K-3Ymono / monoYYmini3.0---
14.
 
Sony A7S IIYstereo / monoYYmicro2.0YY-
15.
 
Sony A7Ystereo / monoYYmicro2.0YY-
16.
 
Sony A7RYstereo / monoYYmicro2.0YY-
17.
 
Sony RX1RYstereo / monoY-mini2.0---

Studio photographers will appreciate that the Pentax K-3 III (unlike the A7S) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.

Travel and landscape photographers will find it useful that the K-3 III has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.

The K-3 III is a recent model that features in the current product line-up of Pentax. 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 Pentax and Sony websites.

Review summary

So how do things add up? Is there a clear favorite between the Pentax K-3 III and the Sony A7S? Which camera is better? The listing below highlights the relative strengths of the two models.

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Arguments in favor of the Pentax K-3 III:

  • More detail: Offers more megapixels (25.6 vs 12MP) with a 46% higher linear resolution.
  • 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.
  • Better video: Provides higher definition movie capture (4K/30p vs 1080/60p).
  • Brighter framing: Features an optical viewfinder for clear, lag-free composition.
  • Easier setting verification: Features an LCD display on top to control shooting parameters.
  • Larger screen: Has a bigger rear LCD (3.2" vs 3.0") for image review and settings control.
  • More detailed LCD: Has a higher resolution rear screen (1620k vs 921k dots).
  • Fewer buttons to press: Is equipped with a touch-sensitive rear screen to facilitate handling.
  • Faster burst: Shoots at higher frequency (12 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 (800 versus 380) on a single battery charge.
  • Sharper images: Has hand-shake reducing image stabilization built-in.
  • Easier geotagging: Features an internal GPS sensor to log localization data.
  • Faster data transfer: Supports a more advanced USB protocol (3.2 vs 2.0).
  • Easier wireless transfer: Supports Bluetooth for image sharing without cables.
  • 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.
  • 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 6 years and 11 months of technical progress since the A7S launch.

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Advantages of the Sony Alpha A7S:

  • Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
  • More framing info: Has an electronic viewfinder that displays shooting data.
  • Larger viewfinder image: Features a viewfinder with a higher magnification (0.71x vs 0.70x).
  • 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 135x104mm) and will fit more readily into a bag.
  • Less heavy: Has a lower weight (by 331g or 40 percent) and is thus easier to take along.
  • Easier travel charging: Can be conveniently charged via its USB port.
  • More legacy lens friendly: Can use many non-native lenses via adapters.
  • Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
  • More heavily discounted: Has been around for much longer (launched in April 2014).

If the number of relative strengths (bullet points above) is taken as a guide, the K-3 III is the clear winner of the match-up (21 : 11 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. 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.

K-3 III 21:11 A7S

How about other alternatives? Do the specifications of the Pentax K-3 III and the Sony A7S 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 technical specifications can provide a useful overview of the capabilities of different cameras, it remains partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the K-3 III or the A7S. 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.

Expert reviews

This is why hands-on reviews by experts are important. The adjacent summary-table relays the overall verdicts of several of the most popular camera review sites (amateurphotographer [AP], cameralabs [CL], digitalcameraworld [DCW], 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.

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Expert Camera Reviews
     Camera 
 Model 
 AP 
 score 
 CL 
 score 
 DCW 
 score 
 DPR 
 score 
 EPZ 
 score 
 PB 
 score 
Camera
Launch
Launch
Price (USD)
Street
Price
1.
 
Pentax K-3 III4/5..3/5..4.5/5.. Mar 2021 1,999 i
2.
 
Sony A7S4/5....86/1004.5/55/5 Apr 2014 2,499i
3.
 
Fujifilm X-T45/5+ +5/588/1005/55/5 Feb 2020 1,699 i
4.
 
Fujifilm X-H1..+5/586/1004.5/54.5/5 Feb 2018 1,899 i
5.
 
Nikon D7805/5..5/587/1004.5/54.5/5 Jan 2020 2,299 i
6.
 
Nikon Z6 II4.5/5..4/589/1004.5/54.5/5 Oct 2020 1,999 i
7.
 
Nikon Z65/5..5/589/1004.5/55/5 Aug 2018 1,999i
8.
 
Nikon D7505/5+ +4/590/1004.5/54.5/5 Sep 2014 2,299i
9.
 
Panasonic S54.5/5+ +4.5/588/1004.5/54.5/5 Sep 2020 1,999 i
10.
 
Pentax KP4/5..3/582/1005/54.5/5 Jan 2017 1,099 i
11.
 
Pentax K-704.5/5....79/1004.5/54.5/5 Jun 2016 649 i
12.
 
Pentax K-3 II4.5/5......5/55/5 Apr 2015 1,099i
13.
 
Pentax K-34/5....83/1005/55/5 Oct 2013 1,299i
14.
 
Sony A7S II5/5+....4.5/55/5 Sep 2015 2,999i
15.
 
Sony A75/5+ +..80/1005/55/5 Oct 2013 1,699i
16.
 
Sony A7R5/5+ +..82/1004.5/55/5 Oct 2013 2,299i
17.
 
Sony RX1R5/5......4/54.5/5 Jun 2013 2,799i
Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.

The review scores listed above should be treated with care, though. The ratings are only valid when referring to cameras in the same category and of the same age. Hence, a score should always be seen in the context of the camera's market launch date and its price, and comparisons of ratings among very different cameras or across long time periods have little meaning. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.

Pentax K-3 III:
Check Amazon price
Sony A7S:
Check Ebay offers

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. Alternatively, you can follow any of the listed hyperlinks for comparisons that others found interesting.

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    Specifications: Pentax K-3 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 Specifications
    Camera Model Pentax K-3 III Sony A7S
    Camera Type Digital single lens reflex Mirrorless system camera
    Camera Lens Pentax K mount lenses Sony E mount lenses
    Launch Date March 2021 April 2014
    Launch Price USD 1,999 USD 2,499
    Sensor Specs Pentax K-3 III Sony A7S
    Sensor Technology CMOS CMOS
    Sensor Format APS-C Sensor Full Frame Sensor
    Sensor Size 23.3 x 15.5 mm 35.8 x 23.9 mm
    Sensor Area 361.15 mm2 855.62 mm2
    Sensor Diagonal 28 mm 43 mm
    Crop Factor 1.5x 1.0x
    Sensor Resolution 25.6 Megapixels 12 Megapixels
    Image Resolution 6192 x 4128 pixels 4240 x 2832 pixels
    Pixel Pitch 3.76 μm 8.45 μm
    Pixel Density 7.08 MP/cm2 1.40 MP/cm2
    Moiré control no AA filter Anti-Alias filter
    Movie Capability 4K/30p Video 1080/60p Video
    ISO Setting 100 - 160,000 ISO 100 - 102,400 ISO
    ISO Boost no Enhancement 50 - 409,600 ISO
    Image Processor PRIME V BIONZ X
    DXO Sensor Quality (score) .. 87
    DXO Color Depth (bits) .. 23.9
    DXO Dynamic Range (EV) .. 13.2
    DXO Low Light (ISO) .. 3702
    Screen Specs Pentax K-3 III Sony A7S
    Viewfinder Type Optical viewfinder Electronic viewfinder
    Viewfinder Field of View 100% 100%
    Viewfinder Magnification 0.70x 0.71x
    Viewfinder Resolution 2400k dots
    Top-Level Screen Control Panel no Top Display
    LCD Framing Live View Live View
    Rear LCD Size 3.2inch 3.0inch
    LCD Resolution 1620k dots 921k dots
    LCD Attachment Fixed screen Tilting screen
    Touch Input Touchscreen no Touchscreen
    Shooting Specs Pentax K-3 III Sony A7S
    Focus System Phase-detect AF Contrast-detect AF
    Manual Focusing AidFocus PeakingFocus Peaking
    Max Shutter Speed (mechanical) 1/8000s 1/8000s
    Continuous Shooting 12 shutter flaps/s 5 shutter flaps/s
    Electronic Shutterno E-ShutterYES
    Time-Lapse PhotographyIntervalometer built-inno Intervalometer
    Image StabilizationIn-body stabilizationLens stabilization only
    Fill Flash no On-Board Flash no On-Board Flash
    Storage Medium 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 Pentax K-3 III Sony A7S
    External Flash Hotshoe Hotshoe
    Studio Flash PC Sync socket no PC Sync
    USB Connector USB 3.2 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 no NFC NFC built-in
    Bluetooth Support Bluetooth built-in no Bluetooth
    Geotagging GPS built-in no internal GPS
    Body Specs Pentax K-3 III Sony A7S
    Environmental SealingWeathersealed bodyWeathersealed body
    Battery Type D-LI90 NP-FW50
    Battery Life (CIPA)800 shots per charge380 shots per charge
    In-Camera Charging no USB charging USB charging
    Body Dimensions 135 x 104 x 74 mm
    (5.3 x 4.1 x 2.9 in)
    127 x 94 x 48 mm
    (5.0 x 3.7 x 1.9 in)
    Camera Weight 820 g (28.9 oz) 489 g (17.2 oz)

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    You are here Home  »  CAM-parator  »  Pentax K-3 III vs Sony A7S

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