Pentax K-1 II vs Sony A7S III
The Pentax K-1 II and the Sony Alpha 7S III are two digital cameras that were announced, respectively, in February 2018 and July 2020. The K-1 II is a DSLR, while the A7S III is a mirrorless interchangeable lens camera. Both cameras are equipped with a full frame sensor. The Pentax has a resolution of 36.2 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.
Going beyond this snapshot of core features and characteristics, what are the differences between the Pentax K-1 II and the Sony Alpha 7S III? 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.
An illustration of the physical size and weight of the Pentax K-1 II and the Sony A7S III is provided in the side-by-side display below. The two cameras are presented according to their relative size. Three consecutive views from the front, the top, and the rear side are shown. All width, height and depth measures are rounded to the nearest millimeter.
The K-1 II can be obtained in two different colors (black, silver), while the A7S III 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 A7S III is notably smaller (18 percent) than the Pentax K-1 II. Moreover, the A7S III is markedly lighter (31 percent) than the K-1 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. 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-1 II gets 670 shots out of its D-LI90 battery, while the A7S III can take 600 images on a single charge of its NP-FZ100 power pack. The power pack in the A7S III can be charged via the USB port, which can be very convenient when travelling.
The adjacent table lists the principal physical characteristics of the two cameras alongside a wider set of alternatives. If you want to switch the focus of the display and review another camera pair, you can move across to the CAM-parator tool and choose from the broad selection of possible camera comparisons there.
|1.||Pentax K-1 II||137 mm||110 mm||86 mm||1010 g||670||Y||Feb 2018||1,999|
|2.||Sony A7S III||127 mm||97 mm||81 mm||699 g||600||Y||Jul 2020||3,499|
|3.||Fujifilm X-H1||140 mm||97 mm||86 mm||673 g||310||Y||Feb 2018||1,899|
|4.||Olympus E-5||142 mm||117 mm||75 mm||873 g||750||Y||Sep 2010||1,699|
|5.||Panasonic S1R||149 mm||110 mm||97 mm||1016 g||380||Y||Feb 2019||3,699|
|6.||Panasonic G9||137 mm||97 mm||92 mm||658 g||400||Y||Nov 2017||1,699|
|7.||Panasonic GH5||139 mm||98 mm||87 mm||725 g||410||Y||Jan 2017||1,999|
|8.||Pentax KP||132 mm||101 mm||76 mm||703 g||390||Y||Jan 2017||1,099|
|9.||Pentax K-1||137 mm||110 mm||86 mm||1010 g||760||Y||Feb 2016||1,799|
|10.||Sony A7R IV||129 mm||96 mm||78 mm||665 g||670||Y||Jul 2019||3,499|
|11.||Sony A7R III||127 mm||96 mm||74 mm||650 g||650||Y||Oct 2017||3,199|
|12.||Sony A9||127 mm||96 mm||63 mm||673 g||650||Y||Apr 2017||4,499|
|13.||Sony RX10 IV||133 mm||94 mm||145 mm||1095 g||400||Y||Sep 2017||1,699|
|14.||Sony A99 II||143 mm||104 mm||76 mm||849 g||490||Y||Sep 2016||3,199|
|15.||Sony A7R II||127 mm||96 mm||60 mm||625 g||290||Y||Jun 2015||3,199|
|16.||Sony A7S II||127 mm||96 mm||60 mm||627 g||370||Y||Sep 2015||2,999|
|Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.|
Any camera decision will obviously take relative prices into account. The retail prices at the time of the camera’s release place the model in the market relative to other models in the producer’s line-up and the competition. The K-1 II was launched at a markedly lower price (by 43 percent) than the A7S III, 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 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 A7S III is 2 percent smaller. 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 36.2MP, the K-1 II offers a higher resolution than the A7S III (12MP), but the K-1 II has smaller individual pixels (pixel pitch of 4.88μm versus 8.40μm for the A7S III). Moreover, the A7S III is a much more recent model (by 2 years and 5 months) than the K-1 II, and its sensor will have benefitted from technological advances during this time that enhance the light gathering capacity of its pixels. Coming back to sensor resolution, it should be mentioned that the K-1 II has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.
The resolution advantage of the Pentax K-1 II implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the K-1 II for good quality output (200 dots per inch) amounts to 36.8 x 24.6 inches or 93.5 x 62.4 cm, for very good quality (250 dpi) 29.4 x 19.6 inches or 74.8 x 49.9 cm, and for excellent quality (300 dpi) 24.5 x 16.4 inches or 62.3 x 41.6 cm. The corresponding values for the Sony A7S III 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 III, the K-1 II has the capacity to capture high quality composite images 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-1 II has a native sensitivity range from ISO 100 to ISO 819200. The corresponding ISO settings for the Sony Alpha 7S III are ISO 80 to ISO 102400, with the possibility to increase the ISO range to 40-409600.
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"). 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 |
|1.||Pentax K-1 II||Full Frame||36.2||7360||4912||1080/60i||..||..||..||..|
|2.||Sony A7S III||Full Frame||12.0||4240||2832||4K/120p||23.7||13.9||2520||86|
|4.||Olympus E-5||Four Thirds||12.2||4032||3024||720/30p||21.6||10.5||519||56|
|5.||Panasonic S1R||Full Frame||46.7||8368||5584||4K/60p||26.4||14.1||3525||100|
|6.||Panasonic G9||Four Thirds||20.2||5184||3888||4K/60p||..||..||..||..|
|7.||Panasonic GH5||Four Thirds||20.2||5184||3888||4K/60p||23.9||13.0||807||77|
|9.||Pentax K-1||Full Frame||36.2||7360||4912||1080/60i||25.4||14.6||3280||96|
|10.||Sony A7R IV||Full Frame||60.2||9504||6336||4K/30p||26.0||14.8||3344||99|
|11.||Sony A7R III||Full Frame||42.2||7952||5304||4K/30p||26.0||14.7||3523||100|
|12.||Sony A9||Full Frame||24.0||6000||4000||4K/30p||24.9||13.3||3517||92|
|13.||Sony RX10 IV||1-inch||20.0||5472||3648||4K/30p||..||..||..||..|
|14.||Sony A99 II||Full Frame||42.2||7952||5304||4K/30p||25.4||13.4||2317||92|
|15.||Sony A7R II||Full Frame||42.2||7952||5304||4K/30p||26.0||13.9||3434||98|
|16.||Sony A7S II||Full Frame||12.0||4240||2832||4K/30p||23.6||13.3||2993||85|
Many modern cameras are not only capable of taking still images, but can also record movies. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, but the A7S III provides a better video resolution than the K-1 II. It can shoot movie footage at 4K/120p, while the Pentax is limited to 1080/60i.
Beyond body and sensor, cameras can and do differ across a range of features. For example, the A7S III has an electronic viewfinder (9440k dots), while the K-1 II 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 III has a higher magnification than the one of the K-1 II (0.91x vs 0.70x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The following table reports on some other key feature differences and similarities of the Pentax K-1 II, the Sony A7S III, and comparable cameras.
|1.||Pentax K-1 II||optical||Y||3.2||1037||full-flex||n||1/8000s||4.4||n||Y|
|2.||Sony A7S III||9440||n||3.0||1440||swivel||Y||1/8000s||10.0||n||Y|
|10.||Sony A7R IV||5760||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|11.||Sony A7R III||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|13.||Sony RX10 IV||2359||Y||3.0||1440||tilting||Y||1/2000s||24.0||Y||Y|
|14.||Sony A99 II||2400||Y||3.0||1229||full-flex||n||1/8000s||12.0||n||Y|
|15.||Sony A7R II||2400||n||3.0||1229||tilting||n||1/8000s||5.0||n||Y|
|16.||Sony A7S II||2400||n||3.0||1229||tilting||n||1/8000s||5.0||n||Y|
One feature that is present on the K-1 II, but is missing on the A7S III 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 A7S III 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 K-1 II 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 A7S 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 Pentax K-1 II 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-1 II writes its imaging data to SDXC cards, while the A7S III uses CFexpress or SDXC cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. The A7S III supports UHS-II cards (on both slots), while the K-1 II 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 Pentax K-1 II and Sony Alpha 7S III and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
| NFC |
|1.||Pentax K-1 II||Y||stereo||mono||Y||Y||micro||2.0||Y||-||-|
|2.||Sony A7S III||Y||stereo||mono||Y||Y||full||3.2||Y||-||Y|
|10.||Sony A7R IV||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|11.||Sony A7R III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|13.||Sony RX10 IV||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
|14.||Sony A99 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||Y|
|15.||Sony A7R II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
|16.||Sony A7S II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
Studio photographers will appreciate that the Pentax K-1 II (unlike the A7S III) 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-1 II has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.
Both the K-1 II and the A7S III are recent models that are part of the current product line-up. The K-1 II replaced the earlier Pentax K-1, while the A7S III followed on from 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.
So how do things add up? Which of the two cameras – the Pentax K-1 II or the Sony A7S III – 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 Pentax K-1 II:
- More detail: Offers more megapixels (36.2 vs 12MP) with a 74% 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.
- 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.
- Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
- Longer lasting: Can take more shots (670 versus 600) on a single battery charge.
- Easier geotagging: Features an internal GPS sensor to log localization data.
- Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
- More affordable: Was introduced into a lower priced category (43 percent cheaper at launch).
- More heavily discounted: Has been available for much longer (launched in February 2018).
Advantages of the Sony Alpha 7S III:
- Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
- Better video: Provides higher definition movie capture (4K/120p vs 1080/60i).
- More framing info: Has an electronic viewfinder that displays shooting data.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.91x vs 0.70x).
- More detailed LCD: Has a higher resolution rear screen (1440k vs 1037k dots).
- Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
- More selfie-friendly: Has an articulated screen that can be turned to be front-facing.
- Faster burst: Shoots at higher frequency (10 vs 4.4 flaps/sec) to capture the decisive moment.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- More compact: Is smaller (127x97mm vs 137x110mm) and will fit more readily into a bag.
- Less heavy: Has a lower weight (by 311g or 31 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.
- Faster data transfer: Supports a more advanced USB protocol (3.2 vs 2.0).
- More solid recording: Has a full-sized HDMI port for a sturdy connection to an external recorder.
- Easier wireless transfer: Supports Bluetooth for image sharing without cables.
- Faster buffer clearing: Supports a more advanced SD data transfer standard (UHS-II vs UHS-I).
- More modern: Reflects 2 years and 5 months of technical progress since the K-1 II launch.
If the count of individual advantages (bullet points above) is taken as a guide, the A7S III is the clear winner of the contest (18 : 12 points). However, the relevance of individual strengths will vary across photographers, so that you might want to apply your own weighing scheme to the summary points when reflecting and deciding 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.
How about other alternatives? Do the specifications of the Pentax K-1 II and the Sony A7S III 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 specs-based evaluation of cameras can be instructive in revealing their potential as photographic tools, it remains partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the K-1 II or the A7S III. 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 where reviews by experts come in. The adjacent summary-table relays the overall verdicts of several of the most popular 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.||Pentax K-1 II||..||..||79/100||4.5/5||4.5/5||Feb 2018||1,999|
|2.||Sony A7S III||..||+ +||91/100||4.5/5||5/5||Jul 2020||3,499|
|3.||Fujifilm X-H1||..||+||86/100||4.5/5||4.5/5||Feb 2018||1,899|
|4.||Olympus E-5||4/5||..||75/100||4/5||4.5/5||Sep 2010||1,699|
|5.||Panasonic S1R||4.5/5||..||89/100||4.5/5||4.5/5||Feb 2019||3,699|
|6.||Panasonic G9||..||+ +||85/100||5/5||5/5||Nov 2017||1,699|
|7.||Panasonic GH5||4.5/5||+ +||85/100||4.5/5||5/5||Jan 2017||1,999|
|8.||Pentax KP||4/5||..||82/100||5/5||4.5/5||Jan 2017||1,099|
|9.||Pentax K-1||5/5||..||84/100||5/5||5/5||Feb 2016||1,799|
|10.||Sony A7R IV||5/5||+||91/100||4.5/5||5/5||Jul 2019||3,499|
|11.||Sony A7R III||..||+ +||90/100||4.5/5||5/5||Oct 2017||3,199|
|12.||Sony A9||5/5||+ +||89/100||5/5||5/5||Apr 2017||4,499|
|13.||Sony RX10 IV||5/5||+||84/100||4.5/5||5/5||Sep 2017||1,699|
|14.||Sony A99 II||..||..||85/100||4.5/5||4.5/5||Sep 2016||3,199|
|15.||Sony A7R II||5/5||+ +||90/100||5/5||5/5||Jun 2015||3,199|
|16.||Sony A7S II||5/5||+||..||4.5/5||5/5||Sep 2015||2,999|
|Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.|
The review scores listed above should be treated with care, though. The assessments were made in relation to similar cameras of the same technological generation. Hence, a score should always be seen in the context of the camera's market launch date and its price, 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? 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: Pentax K-1 II vs Sony A7S III
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||Pentax K-1 II||Sony A7S III|
|Camera Type||Digital single lens reflex||Mirrorless system camera|
|Camera Lens||Pentax K mount lenses||Sony E mount lenses|
|Launch Date||February 2018||July 2020|
|Launch Price||USD 1,999||USD 3,499|
|Sensor Specs||Pentax K-1 II||Sony A7S III|
|Sensor Format||Full Frame Sensor||Full Frame Sensor|
|Sensor Size||35.9 x 24.0 mm||35.6 x 23.8 mm|
|Sensor Area||861.6 mm2||847.28 mm2|
|Sensor Diagonal||43.2 mm||42.8 mm|
|Sensor Resolution||36.2 Megapixels||12 Megapixels|
|Image Resolution||7360 x 4912 pixels||4240 x 2832 pixels|
|Pixel Pitch||4.88 μm||8.40 μm|
|Pixel Density||4.20 MP/cm2||1.42 MP/cm2|
|Moiré control||no AA filter||Anti-Alias filter|
|Movie Capability||1080/60i Video||4K/120p Video|
|ISO Setting||100 - 819,200 ISO||80 - 102,400 ISO|
|ISO Boost||no Enhancement||40 - 409,600 ISO|
|Image Processor||PRIME IV||BIONZ XR|
|DXO Sensor Quality (score)||..||86|
|DXO Color Depth (bits)||..||23.7|
|DXO Dynamic Range (EV)||..||13.9|
|DXO Low Light (ISO)||..||2520|
|Screen Specs||Pentax K-1 II||Sony A7S III|
|Viewfinder Type||Optical viewfinder||Electronic viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||9440k dots|
|Top-Level Screen||Control Panel||no Top Display|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.2inch||3.0inch|
|LCD Resolution||1037k dots||1440k dots|
|LCD Attachment||Fully flexible screen||Swivel screen|
|Touch Input||no Touchscreen||Touchscreen|
|Shooting Specs||Pentax K-1 II||Sony A7S III|
|Focus System||Phase-detect AF||Contrast-detect AF|
|Manual Focusing Aid||Focus Peaking||Focus Peaking|
|Max Shutter Speed (mechanical)||1/8000s||1/8000s|
|Continuous Shooting||4.4 shutter flaps/s||10 shutter flaps/s|
|Shutter Life Expectancy||300 000 actuations||200 000 actuations|
|Electronic Shutter||no E-Shutter||YES|
|Time-Lapse Photography||Intervalometer built-in||no Intervalometer|
|Image Stabilization||In-body stabilization||In-body stabilization|
|Fill Flash||no On-Board Flash||no On-Board Flash|
|Storage Medium||SDXC cards||CFexpress or SDXC cards|
|Second Storage Option||Dual card slots||Dual card slots|
|UHS card support||UHS-I||Dual UHS-II|
|Connectivity Specs||Pentax K-1 II||Sony A7S III|
|Studio Flash||PC Sync socket||no PC Sync|
|USB Connector||USB 2.0||USB 3.2|
|HDMI Port||micro HDMI||full HDMI|
|Microphone Port||External MIC port||External MIC port|
|Headphone Socket||Headphone port||Headphone port|
|Wifi Support||Wifi built-in||Wifi built-in|
|Bluetooth Support||no Bluetooth||Bluetooth built-in|
|Geotagging||GPS built-in||no internal GPS|
|Body Specs||Pentax K-1 II||Sony A7S III|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||670 shots per charge||600 shots per charge|
|In-Camera Charging||no USB charging||USB charging|
137 x 110 x 86 mm
(5.4 x 4.3 x 3.4 in)
127 x 97 x 81 mm
(5.0 x 3.8 x 3.2 in)
|Camera Weight||1010 g (35.6 oz)||699 g (24.7 oz)|
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