Pentax K-3 II vs Sony A9
The Pentax K-3 II and the Sony Alpha A9 are two digital cameras that were announced, respectively, in April 2015 and April 2017. The K-3 II is a DSLR, while the A9 is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (K-3 II) and a full frame (A9) sensor. The Pentax has a resolution of 24.1 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.
|Pentax K-3 II||Sony A9|
|Digital single lens reflex||Mirrorless system camera|
|Pentax K mount lenses||Sony E mount lenses|
|24.1 MP, APS-C Sensor||24 MP, Full Frame Sensor|
|1080/60i Video||4K/30p Video|
|ISO 100-51200||ISO 100-51200 (50-204800)|
|Optical viewfinder||Electronic viewfinder (3686k dots)|
|3.2" LCD, 1037k dots||3.0" LCD, 1440k dots|
|Fixed screen (not touch-sensitive)||Tilting touchscreen|
|8.3 shutter flaps per second||20 shutter flaps per second|
|In-body stabilization||In-body stabilization|
|Weathersealed body||Weathersealed body|
|720 shots per battery charge||650 shots per battery charge|
|131 x 100 x 77 mm, 800 g||127 x 96 x 63 mm, 673 g|
Going beyond this snapshot of core features and characteristics, what are the differences between the Pentax K-3 II and the Sony Alpha A9? 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: Pentax K-3 II vs Sony A9
The physical size and weight of the Pentax K-3 II and the Sony A9 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 dimensions are rounded to the nearest millimeter.
The K-3 II can be obtained in two different colors (black, silver), while the A9 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 is notably smaller (7 percent) than the Pentax K-3 II. Moreover, the A9 is markedly lighter (16 percent) than the K-3 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-3 II gets 720 shots out of its D-LI90 battery, while the A9 can take 650 images on a single charge of its NP-FZ100 power pack. The power pack in the A9 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. In case you want to display and compare another camera duo, just click on the right or left arrow next to the camera that you would like to inspect. Alternatively, you can also use the CAM-parator to select your camera combination among a larger number of options.
|Pentax K-3 II»||5.2 in||3.9 in||3.0 in||28.2 oz||720||Y||Apr 2015||1,099||Pentax K-3 II|
|Sony A9«||5.0 in||3.8 in||2.5 in||23.7 oz||650||Y||Apr 2017||4,499||Sony A9|
|Canon 80D« »||5.5 in||4.1 in||3.1 in||25.8 oz||960||Y||Feb 2016||1,199||Canon 80D|
|Nikon Z6« »||5.3 in||4.0 in||2.6 in||23.8 oz||310||Y||Aug 2018||1,999||Nikon Z6|
|Nikon D7200« »||5.4 in||4.2 in||3.0 in||27.0 oz||1110||Y||Mar 2015||1,199||-||Nikon D7200|
|Panasonic GH5« »||5.5 in||3.9 in||3.4 in||25.6 oz||410||Y||Jan 2017||1,999||Panasonic GH5|
|Panasonic GX8« »||5.2 in||3.1 in||2.5 in||17.2 oz||330||Y||Jul 2015||1,199||-||Panasonic GX8|
|Pentax KP« »||5.2 in||4.0 in||3.0 in||24.8 oz||390||Y||Jan 2017||1,099||Pentax KP|
|Pentax K-70« »||5.0 in||3.7 in||2.9 in||24.3 oz||410||Y||Jun 2016||649||Pentax K-70|
|Pentax K-3« »||5.2 in||3.9 in||3.0 in||28.2 oz||560||Y||Oct 2013||1,299||-||Pentax K-3|
|Pentax K-5« »||5.2 in||3.8 in||2.9 in||26.8 oz||740||Y||Sep 2010||1,099||-||Pentax K-5|
|Sony A7 III« »||5.0 in||3.8 in||2.9 in||22.9 oz||610||Y||Feb 2018||1,999||Sony A7 III|
|Sony A7R III« »||5.0 in||3.8 in||2.9 in||22.9 oz||650||Y||Oct 2017||3,199||Sony A7R III|
|Sony A6300« »||4.7 in||2.6 in||1.9 in||14.3 oz||400||Y||Feb 2016||999||-||Sony A6300|
|Sony A6500« »||4.7 in||2.6 in||2.1 in||16.0 oz||350||Y||Oct 2016||1,399||Sony A6500|
|Sony RX10 II« »||5.1 in||3.5 in||4.0 in||28.7 oz||400||Y||Jun 2015||1,299||-||Sony RX10 II|
|Sony A7 II« »||5.0 in||3.8 in||2.4 in||21.1 oz||350||Y||Nov 2014||1,999||-||Sony A7 II|
|Note: Measurements and pricing do not include easily detachable parts, such as interchangeable lenses or optional viewfinders.|
Any camera decision will obviously take relative prices into account. The manufacturer’s suggested retail prices give an idea on the placement of the camera in the maker’s lineup and the broader market. The K-3 II was launched at a markedly lower price (by 76 percent) than the A9, 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.
Sensor comparison: Pentax K-3 II vs Sony A9
The size of the imaging sensor is a crucial determinant 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. 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 more expensive and lead to bigger and heavier cameras and lenses.
Of the two cameras under consideration, the Pentax K-3 II features an APS-C sensor and the Sony A9 a full frame sensor. The sensor area in the A9 is 131 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.
Despite having a smaller sensor, the Pentax K-3 II offers a higher resolution of 24.1 megapixels, compared with 24 MP of the Sony A9. 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 3.90μm versus 5.94μm for the A9). Moreover, it should be noted that the A9 is a somewhat more recent model (by 1 year and 11 months) than the K-3 II, and its sensor might have benefitted from technological advances during this time that further enhance the light gathering capacity of its pixel-units. Coming back to sensor resolution, it should be mentioned that the K-3 II has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.
The A9 has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.
Unlike the A9, the K-3 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-3 II has a native sensitivity range from ISO 100 to ISO 51200. The corresponding ISO settings for the Sony Alpha A9 are ISO 100 to ISO 51200, with the possibility to increase the ISO range to 50-204800.
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 consideration, the A9 offers substantially better image quality than the K-3 II (overall score 12 points higher). The advantage is based on 1.3 bits higher color depth, 0.3 EV of lower dynamic range, and 1.7 stops in additional low light sensitivity. The table below summarizes the physical sensor characteristics and sensor quality findings and compares them across a set of similar cameras.
|Pentax K-3 II»||APS-C||24.1||6016||4000||1080/60i||23.6||13.6||1106||80||Pentax K-3 II|
|Sony A9«||Full Frame||24.0||6000||4000||4K/30p||24.9||13.3||3517||92||Sony A9|
|Canon 80D« »||APS-C||24.0||6000||4000||1080/60p||23.6||13.2||1135||79||Canon 80D|
|Nikon Z6« »||Full Frame||24.3||6048||4024||4K/30p||25.3||14.3||3299||95||Nikon Z6|
|Nikon D7200« »||APS-C||24.0||6000||4000||1080/60p||24.5||14.6||1333||87||Nikon D7200|
|Panasonic GH5« »||Four Thirds||20.2||5184||3888||4K/60p||23.9||13.0||807||77||Panasonic GH5|
|Panasonic GX8« »||Four Thirds||20.2||5184||3888||4K/30p||23.5||12.6||806||75||Panasonic GX8|
|Pentax KP« »||APS-C||24.1||6016||4000||1080/60i||-||-||-||-||Pentax KP|
|Pentax K-70« »||APS-C||24.0||6000||4000||1080/60i||-||-||-||-||Pentax K-70|
|Pentax K-3« »||APS-C||24.1||6016||4000||1080/60i||23.7||13.4||1216||80||Pentax K-3|
|Pentax K-5« »||APS-C||16.1||4928||3264||1080/25p||23.7||14.1||1162||82||Pentax K-5|
|Sony A7 III« »||Full Frame||24.0||6000||4000||4K/30p||25.0||14.7||3730||96||Sony A7 III|
|Sony A7R III« »||Full Frame||42.2||7952||5304||4K/30p||26.0||14.7||3523||100||Sony A7R III|
|Sony A6300« »||APS-C||24.0||6000||4000||4K/30p||24.4||13.7||1437||85||Sony A6300|
|Sony A6500« »||APS-C||24.0||6000||4000||4K/30p||24.5||13.7||1405||85||Sony A6500|
|Sony RX10 II« »||1-inch||20.0||5472||3648||4K/30p||23.0||12.6||531||70||Sony RX10 II|
|Sony A7 II« »||Full Frame||24.0||6000||4000||1080/60p||24.9||13.6||2449||90||Sony A7 II|
Many modern cameras are not only capable of taking still images, but can also record movies. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, but the A9 provides a better video resolution than the K-3 II. It can shoot movie footage at 4K/30p, while the Pentax is limited to 1080/60i.
Feature comparison: Pentax K-3 II vs Sony A9
Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A9 has an electronic viewfinder (3686k dots), while the K-3 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 has a higher magnification than the one of the K-3 II (0.78x vs 0.63x), 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-3 II, the Sony A9, and comparable cameras.
|Pentax K-3 II»||optical||Y||3.2||1037||fixed||n||1/8000s||8.3||n||Y||Pentax K-3 II|
|Sony A9«||3686||n||3.0||1440||tilting||Y||1/8000s||20.0||n||Y||Sony A9|
|Canon 80D« »||optical||Y||3.0||1040||swivel||Y||1/8000s||7.0||Y||n||Canon 80D|
|Nikon Z6« »||3690||Y||3.2||2100||tilting||Y||1/8000s||12.0||n||Y||Nikon Z6|
|Nikon D7200« »||optical||Y||3.2||1229||fixed||n||1/8000s||6.0||Y||n||Nikon D7200|
|Panasonic GH5« »||3680||n||3.2||1620||swivel||Y||1/8000s||12.0||n||Y||Panasonic GH5|
|Panasonic GX8« »||2360||n||3.0||1040||swivel||Y||1/8000s||10.0||n||Y||Panasonic GX8|
|Pentax KP« »||optical||n||3.0||921||tilting||n||1/6000s||7.0||Y||Y||Pentax KP|
|Pentax K-70« »||optical||n||3.0||921||swivel||n||1/6000s||6.0||Y||Y||Pentax K-70|
|Pentax K-3« »||optical||Y||3.2||1037||fixed||n||1/8000s||8.3||Y||Y||Pentax K-3|
|Pentax K-5« »||optical||Y||3.0||921||fixed||n||1/8000s||7.0||Y||Y||Pentax K-5|
|Sony A7 III« »||2359||n||3.0||922||tilting||Y||1/8000s||10.0||n||Y||Sony A7 III|
|Sony A7R III« »||3686||n||3.0||1440||tilting||Y||1/8000s||10.0||n||Y||Sony A7R III|
|Sony A6300« »||2359||n||3.0||922||tilting||n||1/4000s||11.0||Y||n||Sony A6300|
|Sony A6500« »||2359||n||3.0||922||tilting||Y||1/4000s||11.0||Y||Y||Sony A6500|
|Sony RX10 II« »||2359||Y||3.0||1229||tilting||n||1/3200s||14.0||Y||Y||Sony RX10 II|
|Sony A7 II« »||2400||n||3.0||1230||tilting||n||1/8000s||5.0||n||Y||Sony A7 II|
One feature that is present on the K-3 II, but is missing on the A9 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 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 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-3 II writes its imaging data to SDXC cards, while the A9 uses SDXC or Memory Stick PRO Duo cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. The A9 supports UHS-II cards (on its first slot), while the K-3 II can use UHS-I cards.
Connectivity comparison: Pentax K-3 II vs Sony A9
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 II and Sony Alpha A9 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
|Pentax K-3 II»||Y||mono||mono||Y||Y||mini||3.0||-||-||-||Pentax K-3 II|
|Sony A9«||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||Y||Sony A9|
|Canon 80D« »||Y||stereo||mono||Y||Y||mini||2.0||Y||Y||-||Canon 80D|
|Nikon Z6« »||Y||stereo||mono||Y||Y||micro||3.1||Y||-||Y||Nikon Z6|
|Nikon D7200« »||Y||stereo||mono||Y||Y||mini||2.0||Y||Y||-||Nikon D7200|
|Panasonic GH5« »||Y||stereo||mono||Y||Y||full||3.1||Y||-||Y||Panasonic GH5|
|Panasonic GX8« »||Y||stereo||mono||Y||-||micro||2.0||Y||Y||-||Panasonic GX8|
|Pentax KP« »||Y||stereo||mono||Y||-||-||2.0||Y||-||-||Pentax KP|
|Pentax K-70« »||Y||stereo||mono||Y||-||mini||2.0||Y||-||-||Pentax K-70|
|Pentax K-3« »||Y||mono||mono||Y||Y||mini||3.0||-||-||-||Pentax K-3|
|Pentax K-5« »||Y||stereo||mono||Y||-||mini||2.0||-||-||-||Pentax K-5|
|Sony A7 III« »||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y||Sony A7 III|
|Sony A7R III« »||Y||stereo||mono||Y||Y||micro||3.1||Y||Y||Y||Sony A7R III|
|Sony A6300« »||Y||stereo||mono||Y||-||micro||2.0||Y||Y||-||Sony A6300|
|Sony A6500« »||Y||stereo||mono||Y||-||micro||2.0||Y||Y||-||Sony A6500|
|Sony RX10 II« »||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-||Sony RX10 II|
|Sony A7 II« »||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-||Sony A7 II|
It is notable that the A9 offers wifi support, which can be a very convenient means to transfer image data to an off-camera location. In contrast, the K-3 II does not offer wifi capability.
Studio photographers will appreciate that the Pentax K-3 II (unlike the A9) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
Both the K-3 II and the A9 are recent models that are part of the current product line-up. The K-3 II replaced the earlier Pentax K-3, while the A9 does not have a direct predecessor. 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: Pentax K-3 II vs Sony A9
So what is the bottom line? Is there a clear favorite between the Pentax K-3 II and the Sony A9? Which camera is better? A synthesis of the relative strong points of each of the models is listed below.
Reasons to prefer the Pentax K-3 II:
- 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 (720 versus 650) on a single battery charge.
- Faster data transfer: Supports a more advanced USB protocol (3.0 vs 2.0).
- Better studio light control: Has a PC Sync socket to connect to professional strobe lights.
- More affordable: Was introduced into a lower priced category (76 percent cheaper at launch).
- More heavily discounted: Has been on the market for longer (launched in April 2015).
Arguments in favor of the Sony Alpha A9:
- Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
- Better image quality: Scores substantially higher (12 points) in the DXO overall evaluation.
- Richer colors: Generates noticeably more natural colors (1.3 bits more color depth).
- Better low-light sensitivity: Can shoot in dim conditions (1.7 stops ISO advantage).
- 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 0.63x).
- More detailed LCD: Has a higher resolution rear screen (1440k vs 1037k dots).
- More flexible LCD: Has a tilting screen for odd-angle shots in landscape orientation.
- Fewer buttons to press: Has a touchscreen to facilitate handling and shooting adjustments.
- Faster burst: Shoots at higher frequency (20 vs 8.3 flaps/sec) to capture the decisive moment.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- Less heavy: Has a lower weight (by 127g or 16 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 file upload: Has wifi built in for automatic backup or image transfer to the web.
- 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 11 months) more recently.
If the count of individual advantages (bullet points above) is taken as a guide, the A9 is the clear winner of the contest (20 : 11 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-3 II and the Sony A9 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 says little about, for example, the shooting experience and imaging performance of the K-3 II and the A9 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.
Expert reviews: Pentax K-3 II vs Sony A9
This is where reviews by experts come in. The table below provides a synthesis of the camera assessments of some of the best known photo-gear review sites (cameralabs, dpreview, ephotozine, imaging-resource, and photographyblog). 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.
|Pentax K-3 II»||-||-||5/5||4.5/5||5/5||Apr 2015||1,099||Pentax K-3 II|
|Sony A9«||+ +||89/100||5/5||5/5||5/5||Apr 2017||4,499||Sony A9|
|Canon 80D« »||+ +||84/100||4.5/5||4.5/5||4.5/5||Feb 2016||1,199||Canon 80D|
|Nikon Z6« »||-||-||4.5/5||-||5/5||Aug 2018||1,999||Nikon Z6|
|Nikon D7200« »||+ +||84/100||4.5/5||4/5||4.5/5||Mar 2015||1,199||-||Nikon D7200|
|Panasonic GH5« »||+ +||85/100||4.5/5||5/5||5/5||Jan 2017||1,999||Panasonic GH5|
|Panasonic GX8« »||+||82/100||4.5/5||5/5||4.5/5||Jul 2015||1,199||-||Panasonic GX8|
|Pentax KP« »||-||82/100||5/5||-||4.5/5||Jan 2017||1,099||Pentax KP|
|Pentax K-70« »||-||79/100||4.5/5||4/5||4.5/5||Jun 2016||649||Pentax K-70|
|Pentax K-3« »||-||83/100||5/5||4.5/5||5/5||Oct 2013||1,299||-||Pentax K-3|
|Pentax K-5« »||-||83/100||5/5||4.5/5||4.5/5||Sep 2010||1,099||-||Pentax K-5|
|Sony A7 III« »||+ +||89/100||5/5||5/5||5/5||Feb 2018||1,999||Sony A7 III|
|Sony A7R III« »||+ +||90/100||4.5/5||5/5||5/5||Oct 2017||3,199||Sony A7R III|
|Sony A6300« »||+||85/100||5/5||5/5||5/5||Feb 2016||999||-||Sony A6300|
|Sony A6500« »||+ +||85/100||4.5/5||5/5||4.5/5||Oct 2016||1,399||Sony A6500|
|Sony RX10 II« »||+ +||82/100||4.5/5||4.5/5||4/5||Jun 2015||1,299||-||Sony RX10 II|
|Sony A7 II« »||+||82/100||4.5/5||5/5||5/5||Nov 2014||1,999||-||Sony A7 II|
|Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (-) not available.|
Care should be taken when interpreting the review scores above, though. The assessments were made in relation to similar cameras of the same technological generation. Thus, a score needs to be put into the context of the launch date and the launch price 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, 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 make your choice using the following search menu. Alternatively, you can follow any of the listed hyperlinks for comparisons that others found interesting.
- Canon 5D Mark IV vs Pentax K-3 II
- Canon RP vs Sony A9
- Canon SL1 vs Pentax K-3 II
- Hasselblad X1D vs Sony A9
- Olympus PEN-F vs Pentax K-3 II
- Panasonic G85 vs Sony A9
- Panasonic LX15 vs Pentax K-3 II
- Pentax K-3 II vs Sony RX10 IV
- Pentax K-5 vs Sony A9
- Sony A77 vs Sony A9
- Sony A7R II vs Sony A9
- Sony A9 vs Sony WX800
Specifications: Pentax K-3 II vs Sony A9
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-3 II||Sony A9|
|Camera Type||Digital single lens reflex||Mirrorless system camera|
|Camera Lens||Pentax K mount lenses||Sony E mount lenses|
|Launch Date||April 2015||April 2017|
|Launch Price||USD 1099||USD 4499|
|Sensor Specs||Pentax K-3 II||Sony A9|
|Sensor Format||APS-C Sensor||Full Frame Sensor|
|Sensor Size||23.5 x 15.6 mm||35.6 x 23.8 mm|
|Sensor Area||366.6 mm2||847.28 mm2|
|Sensor Diagonal||28.2 mm||42.8 mm|
|Sensor Resolution||24.1 Megapixels||24 Megapixels|
|Image Resolution||6016 x 4000 pixels||6000 x 4000 pixels|
|Pixel Pitch||3.90 μm||5.94 μm|
|Pixel Density||6.56 MP/cm2||2.83 MP/cm2|
|Moiré control||no AA filter||Anti-Alias filter|
|Movie Capability||1080/60i Video||4K/30p Video|
|ISO Setting||100-51200 ISO||100-51200 ISO|
|ISO Boost||no Enhancement||50-204800 ISO|
|Image Processor||PRIME III||BIONZ X|
|DXO Sensor Quality (score)||80||92|
|DXO Color Depth (bits)||23.6||24.9|
|DXO Dynamic Range (EV)||13.6||13.3|
|DXO Low Light (ISO)||1106||3517|
|Screen Specs||Pentax K-3 II||Sony A9|
|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||3.2 inch||3.0 inch|
|LCD Resolution||1037k dots||1440k dots|
|LCD Attachment||Fixed screen||Tilting screen|
|Touch Input||no Touchscreen||Touchscreen|
|Shooting Specs||Pentax K-3 II||Sony A9|
|Autofocus System||Phase-detect AF||On-Sensor Phase-detect|
|Manual Focusing Aid||Focus Peaking||Focus Peaking|
|Max Shutter Speed (mechanical)||1/8000/s||1/8000/s|
|Continuous Shooting||8.3 shutter flaps/s||20 shutter flaps/s|
|Shutter Life Expectancy||200 000 actuations||500 000 actuations|
|Electronic Shutter||no E-Shutter||up to 1/32000s|
|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||MS or SDXC cards|
|Second Storage Option||Dual card slots||Dual card slots|
|UHS card support||UHS-I||Single UHS-II|
|Connectivity Specs||Pentax K-3 II||Sony A9|
|Studio Flash||PC Sync socket||no PC Sync|
|USB Connector||USB 3.0||USB 2.0|
|HDMI Port||mini HDMI||micro HDMI|
|Microphone Port||External MIC port||External MIC port|
|Headphone Socket||Headphone port||Headphone port|
|Wifi Support||no Wifi||Wifi built-in|
|Near-Field Communication||no NFC||NFC built-in|
|Bluetooth Support||no Bluetooth||Bluetooth built-in|
|Body Specs||Pentax K-3 II||Sony A9|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Type||D-LI90 power pack||NP-FZ100 power pack|
|Battery Life (CIPA)||720 shots per charge||650 shots per charge|
|In-Camera Charging||no USB charging||USB charging|
131 x 100 x 77 mm
(5.2 x 3.9 x 3.0 in)
127 x 96 x 63 mm
(5.0 x 3.8 x 2.5 in)
|Camera Weight||800 g (28.2 oz)||673 g (23.7 oz)|
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