Pentax K-1 II vs Sony A9 II
The Pentax K-1 II and the Sony Alpha A9 II are two digital cameras that were officially introduced, respectively, in February 2018 and October 2019. The K-1 II is a DSLR, while the A9 II 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 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 Pentax K-1 II and the Sony Alpha A9 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 Pentax K-1 II and the Sony A9 II are illustrated 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 A9 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 A9 II is notably smaller (18 percent) than the Pentax K-1 II. Moreover, the A9 II is markedly lighter (33 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 A9 II can take 690 images on a single charge of its NP-FZ100 power pack. The power pack in the A9 II 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.
|1.||Pentax K-1 II||137 mm||110 mm||86 mm||1010 g||670||Y||Feb 2018||1,999|
|2.||Sony A9 II||129 mm||96 mm||76 mm||678 g||690||Y||Oct 2019||4,499|
|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 A7S III||127 mm||97 mm||81 mm||699 g||600||Y||Jul 2020||3,499|
|11.||Sony A7C||124 mm||71 mm||60 mm||509 g||740||Y||Sep 2020||1,799|
|12.||Sony A7R IV||129 mm||96 mm||78 mm||665 g||670||Y||Jul 2019||3,499|
|13.||Sony A7 III||127 mm||96 mm||74 mm||650 g||610||Y||Feb 2018||1,999|
|14.||Sony A7R III||127 mm||96 mm||74 mm||650 g||650||Y||Oct 2017||3,199|
|15.||Sony A9||127 mm||96 mm||63 mm||673 g||650||Y||Apr 2017||4,499|
|16.||Sony RX10 IV||133 mm||94 mm||145 mm||1095 g||400||Y||Sep 2017||1,699|
|17.||Sony A99 II||143 mm||104 mm||76 mm||849 g||490||Y||Sep 2016||3,199|
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 K-1 II was launched at a markedly lower price (by 56 percent) than the A9 II, which puts it into a different market segment. Normally, street prices remain initially close to the MSRP, but after a couple of months, the first discounts appear. 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.
The size of the sensor inside a digital camera is one of the key determinants 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 A9 II 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 A9 II (24MP), but the K-1 II has smaller individual pixels (pixel pitch of 4.88μm versus 5.94μm for the A9 II). Moreover, the A9 II is a somewhat more recent model (by 1 year and 7 months) than the K-1 II, and its sensor might have benefitted from technological advances during this time that further 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 A9 II are 30 x 20 inches or 76.2 x 50.8 cm for good quality, 24 x 16 inches or 61 x 40.6 cm for very good quality, and 20 x 13.3 inches or 50.8 x 33.9 cm for excellent quality prints.
The A9 II has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.
Unlike the A9 II, 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 A9 II are ISO 100 to ISO 51200, with the possibility to increase the ISO range to 50-204800.
For many cameras, data on sensor performance has been reported by DXO Mark. This service assesses and scores the color depth ("DXO Portrait"), dynamic range ("DXO Landscape"), and low-light sensitivity ("DXO Sports") of camera sensors, and also publishes an overall camera score. The following table provides an overview of the physical sensor characteristics, as well as the sensor quality measurements for a selection of comparators.
| DXO |
|1.||Pentax K-1 II||Full Frame||36.2||7360||4912||1080/60i||..||..||..||..|
|2.||Sony A9 II||Full Frame||24.0||6000||4000||4K/30p||25.0||14.0||3434||93|
|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 A7S III||Full Frame||12.0||4240||2832||4K/120p||23.7||13.9||2520||86|
|11.||Sony A7C||Full Frame||24.0||6000||4000||4K/30p||25.0||14.7||3407||95|
|12.||Sony A7R IV||Full Frame||60.2||9504||6336||4K/30p||26.0||14.8||3344||99|
|13.||Sony A7 III||Full Frame||24.0||6000||4000||4K/30p||25.0||14.7||3730||96|
|14.||Sony A7R III||Full Frame||42.2||7952||5304||4K/30p||26.0||14.7||3523||100|
|15.||Sony A9||Full Frame||24.0||6000||4000||4K/30p||24.9||13.3||3517||92|
|16.||Sony RX10 IV||1-inch||20.0||5472||3648||4K/30p||..||..||..||..|
|17.||Sony A99 II||Full Frame||42.2||7952||5304||4K/30p||25.4||13.4||2317||92|
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 II provides a better video resolution than the K-1 II. It can shoot movie footage at 4K/30p, while the Pentax is limited to 1080/60i.
Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A9 II has an electronic viewfinder (3686k 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 A9 II has a higher magnification than the one of the K-1 II (0.78x vs 0.70x), so that the size of the image transmitted appears closer to the size seen with the naked human eye. The table below summarizes some of the other core capabilities of the Pentax K-1 II and Sony A9 II in connection with corresponding information for a sample of similar cameras.
|1.||Pentax K-1 II||optical||Y||3.2||1037||full-flex||n||1/8000s||4.4||n||Y|
|2.||Sony A9 II||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|10.||Sony A7S III||9440||n||3.0||1440||swivel||Y||1/8000s||10.0||n||Y|
|12.||Sony A7R IV||5760||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|13.||Sony A7 III||2359||n||3.0||922||tilting||Y||1/8000s||10.0||n||Y|
|14.||Sony A7R III||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y|
|16.||Sony RX10 IV||2359||Y||3.0||1440||tilting||Y||1/2000s||24.0||Y||Y|
|17.||Sony A99 II||2400||Y||3.0||1229||full-flex||n||1/8000s||12.0||n||Y|
One feature that is present on the K-1 II, but is missing on the A9 II 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 A9 II 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 and the Sony A9 II both have 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.
Concerning the storage of imaging data, both the K-1 II and the A9 II write their files to SDXC cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. The A9 II 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 A9 II 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 A9 II||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|10.||Sony A7S III||Y||stereo||mono||Y||Y||full||3.2||Y||-||Y|
|12.||Sony A7R IV||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|13.||Sony A7 III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|14.||Sony A7R III||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y|
|16.||Sony RX10 IV||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
|17.||Sony A99 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||Y|
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 K-1 II has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.
Both the K-1 II and the A9 II are recent models that are part of the current product line-up. The K-1 II replaced the earlier Pentax K-1, while the A9 II followed on from the Sony A9. 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 what is the bottom line? Which of the two cameras – the Pentax K-1 II or the Sony A9 II – 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.
Reasons to prefer the Pentax K-1 II:
- More detail: Offers more megapixels (36.2 vs 24MP) with a 23% 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.
- More flexible LCD: Has a full-flex screen for odd-angle shots in portrait or landscape orientation.
- Easier geotagging: Features an internal GPS sensor to log localization data.
- More affordable: Was introduced into a lower priced category (56 percent cheaper at launch).
- More heavily discounted: Has been on the market for longer (launched in February 2018).
Advantages of the Sony Alpha A9 II:
- Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
- Better video: Provides higher definition movie capture (4K/30p vs 1080/60i).
- Better live-view autofocus: Features on-sensor phase-detection for more confident autofocus.
- More framing info: Has an electronic viewfinder that displays shooting data.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.78x 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.
- 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 (129x96mm vs 137x110mm) and will fit more readily into a bag.
- Less heavy: Has a lower weight (by 332g or 33 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 (3.1 vs 2.0).
- Easier device pairing: Supports NFC for fast wireless image transfer over short distances.
- 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: Was introduced somewhat (1 year and 7 months) more recently.
If the count of relative strengths (bullet points above) is taken as a measure, the A9 II is the clear winner of the contest (18 : 10 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 Pentax K-1 II and the Sony A9 II 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 K-1 II and the A9 II 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 (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 A9 II||..||..||90/100||5/5||5/5||Oct 2019||4,499|
|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 A7S III||..||+ +||91/100||4.5/5||5/5||Jul 2020||3,499|
|11.||Sony A7C||3.5/5||..||86/100||4/5||4/5||Sep 2020||1,799|
|12.||Sony A7R IV||5/5||+||91/100||4.5/5||5/5||Jul 2019||3,499|
|13.||Sony A7 III||..||+ +||89/100||5/5||5/5||Feb 2018||1,999|
|14.||Sony A7R III||..||+ +||90/100||4.5/5||5/5||Oct 2017||3,199|
|15.||Sony A9||5/5||+ +||89/100||5/5||5/5||Apr 2017||4,499|
|16.||Sony RX10 IV||5/5||+||84/100||4.5/5||5/5||Sep 2017||1,699|
|17.||Sony A99 II||..||..||85/100||4.5/5||4.5/5||Sep 2016||3,199|
|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. 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? 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 A9 II
|Camera Model||Pentax K-1 II||Sony A9 II|
|Camera Type||Digital single lens reflex||Mirrorless system camera|
|Camera Lens||Pentax K mount lenses||Sony E mount lenses|
|Launch Date||February 2018||October 2019|
|Launch Price||USD 1,999||USD 4,499|
|Sensor Specs||Pentax K-1 II||Sony A9 II|
|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||24 Megapixels|
|Image Resolution||7360 x 4912 pixels||6000 x 4000 pixels|
|Pixel Pitch||4.88 μm||5.94 μm|
|Pixel Density||4.20 MP/cm2||2.83 MP/cm2|
|Moiré control||no AA filter||Anti-Alias filter|
|Movie Capability||1080/60i Video||4K/30p Video|
|ISO Setting||100 - 819,200 ISO||100 - 51,200 ISO|
|ISO Boost||no Enhancement||50 - 204,800 ISO|
|Image Processor||PRIME IV||BIONZ X|
|DXO Sensor Quality (score)||..||93|
|DXO Color Depth (bits)||..||25.0|
|DXO Dynamic Range (EV)||..||14.0|
|DXO Low Light (ISO)||..||3434|
|Screen Specs||Pentax K-1 II||Sony A9 II|
|Viewfinder Type||Optical viewfinder||Electronic viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||3686k 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||Tilting screen|
|Touch Input||no Touchscreen||Touchscreen|
|Shooting Specs||Pentax K-1 II||Sony A9 II|
|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||4.4 shutter flaps/s||10 shutter flaps/s|
|Shutter Life Expectancy||300 000 actuations||500 000 actuations|
|Electronic Shutter||no E-Shutter||up to 1/32000s|
|Time-Lapse Photography||Intervalometer built-in||Intervalometer built-in|
|Image Stabilization||In-body stabilization||In-body stabilization|
|Fill Flash||no On-Board Flash||no On-Board Flash|
|Storage Medium||SDXC cards||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 A9 II|
|Studio Flash||PC Sync socket||PC Sync socket|
|USB Connector||USB 2.0||USB 3.1|
|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||no Bluetooth||Bluetooth built-in|
|Geotagging||GPS built-in||no internal GPS|
|Body Specs||Pentax K-1 II||Sony A9 II|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||670 shots per charge||690 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)
129 x 96 x 76 mm
(5.1 x 3.8 x 3.0 in)
|Camera Weight||1010 g (35.6 oz)||678 g (23.9 oz)|