Pentax K-3 II vs Sony A9 III
The Pentax K-3 II and the Sony Alpha A9 III are two digital cameras that were revealed to the public, respectively, in April 2015 and November 2023. The K-3 II is a DSLR, while the A9 III is a mirrorless interchangeable lens camera. The cameras are based on an APS-C (K-3 II) and a full frame (A9 III) 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.

Check K-3 II offers at
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Check A9 III price at
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Going beyond this snapshot of core features and characteristics, what are the differences between the Pentax K-3 II and the Sony Alpha A9 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.
Body comparison
The physical size and weight of the Pentax K-3 II and the Sony A9 III 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 II can be obtained in two different colors (black, silver), while the A9 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 Pentax K-3 II and the Sony A9 III are of equal size. However, the A9 III is markedly lighter (12 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 Pentax D-LI90 battery, while the A9 III can take 530 images on a single charge of its Sony NP-FZ100 power pack. The power pack in the A9 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. In case you want to display and compare another camera duo, you can use the CAM-parator app to select your camera combination among a large number of options.

| Camera Model |
Camera Width |
Camera Height |
Camera Depth |
Camera Weight |
Battery Life |
Weather Sealing |
Camera Launch |
Launch Price |
Street Price |
||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. | Pentax K-3 II | 131 mm | 100 mm | 77 mm | 800 g | 720 | Y | Apr 2015 | US$ 1 099 | ebay.com | |
| 2. | Sony A9 III | 136 mm | 97 mm | 83 mm | 702 g | 530 | Y | Nov 2023 | US$ 5 999 | amazon.com | |
| 3. | Nikon D7200 | 136 mm | 107 mm | 76 mm | 765 g | 1110 | Y | Mar 2015 | US$ 1 199 | ebay.com | |
| 4. | Pentax K-3 | 131 mm | 100 mm | 77 mm | 800 g | 560 | Y | Oct 2013 | US$ 1 299 | ebay.com | |
| 5. | Pentax K-3 III | 135 mm | 104 mm | 74 mm | 820 g | 800 | Y | Mar 2021 | US$ 1 999 | amazon.com | |
| 6. | Pentax K-5 | 131 mm | 97 mm | 73 mm | 760 g | 740 | Y | Sep 2010 | US$ 1 099 | ebay.com | |
| 7. | Pentax K-5 II | 131 mm | 97 mm | 73 mm | 760 g | 740 | Y | Sep 2012 | US$ 1 099 | ebay.com | |
| 8. | Pentax K-70 | 126 mm | 93 mm | 74 mm | 688 g | 410 | Y | Jun 2016 | US$ 649 | ebay.com | |
| 9. | Pentax KP | 132 mm | 101 mm | 76 mm | 703 g | 390 | Y | Jan 2017 | US$ 1 099 | ebay.com | |
| 10. | Pentax K-S1 | 121 mm | 93 mm | 70 mm | 558 g | 410 | n | Aug 2014 | US$ 749 | ebay.com | |
| 11. | Pentax K-S2 | 123 mm | 91 mm | 73 mm | 678 g | 410 | Y | Feb 2015 | US$ 749 | ebay.com | |
| 12. | Sony A1 II | 136 mm | 97 mm | 83 mm | 743 g | 520 | Y | Nov 2024 | US$ 6 499 | amazon.com | |
| 13. | Sony A7 II | 127 mm | 96 mm | 60 mm | 599 g | 350 | Y | Nov 2014 | US$ 1 999 | ebay.com | |
| 14. | Sony A7 III | 127 mm | 96 mm | 74 mm | 650 g | 610 | Y | Feb 2018 | US$ 1 999 | amazon.com | |
| 15. | Sony A9 | 127 mm | 96 mm | 63 mm | 673 g | 650 | Y | Apr 2017 | US$ 4 499 | ebay.com | |
| 16. | Sony A9 II | 129 mm | 96 mm | 76 mm | 678 g | 690 | Y | Oct 2019 | US$ 4 499 | amazon.com | |
| 17. | Sony A77 II | 143 mm | 104 mm | 81 mm | 647 g | 480 | Y | May 2014 | US$ 1 199 | ebay.com | |
| Note: 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 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 82 percent) than the A9 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.
Sensor comparison
The size of the sensor inside a digital camera is one of the key determinants of image quality. A large sensor will generally have larger individual pixels that offer better low-light sensitivity, provide wider dynamic range, and have richer color-depth than smaller pixels in a sensor of the same technological generation. Moreover, a large sensor camera will give the photographer more control over depth-of-field in the image and, thus, the ability to better isolate a subject from the background. On the downside, larger sensors tend to be associated with larger, more expensive camera bodies and lenses.
Of the two cameras under consideration, the Pentax K-3 II features an APS-C sensor and the Sony A9 III a full frame sensor. The sensor area in the A9 III 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 III. 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 III). Moreover, it should be noted that the A9 III is much more recent (by 8 years and 6 months) than the K-3 II, and its sensor will 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 III has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during live view operation.
Unlike the A9 III, 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 III are ISO 250 to ISO 25600, with the possibility to increase the ISO range to 125-51200.
In terms of underlying technology, the K-3 II is build around a CMOS sensor, while the A9 III uses a Stacked CMOS imager. Both cameras use a Bayer filter for capturing RGB colors on a square grid of photosensors. This arrangement is found in most digital cameras.

For many cameras, data on sensor performance has been reported by DXO Mark. 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 following table provides an overview of the physical sensor characteristics, as well as the sensor quality measurements for a selection of comparators.

| Camera Model |
Sensor Class |
Resolution (MP) |
Horiz. Pixels |
Vert. Pixels |
Video Format |
DXO Portrait |
DXO Landscape |
DXO Sports |
DXO Overall |
||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. | Pentax K-3 II | APS-C | 24.1 | 6016 | 4000 | 1080/60i | 23.6 | 13.6 | 1106 | 80 | |
| 2. | Sony A9 III | Full Frame | 24.0 | 6000 | 4000 | 4K/120p | 25.4 | 14.7 | 3243 | 96 | |
| 3. | Nikon D7200 | APS-C | 24.0 | 6000 | 4000 | 1080/60p | 24.5 | 14.6 | 1333 | 87 | |
| 4. | Pentax K-3 | APS-C | 24.1 | 6016 | 4000 | 1080/60i | 23.7 | 13.4 | 1216 | 80 | |
| 5. | Pentax K-3 III | APS-C | 25.6 | 6192 | 4128 | 4K/30p | 24.2 | 13.7 | 2083 | 85 | |
| 6. | Pentax K-5 | APS-C | 16.1 | 4928 | 3264 | 1080/25p | 23.7 | 14.1 | 1162 | 82 | |
| 7. | Pentax K-5 II | APS-C | 16.1 | 4928 | 3264 | 1080/25p | 23.8 | 14.1 | 1235 | 82 | |
| 8. | Pentax K-70 | APS-C | 24.0 | 6000 | 4000 | 1080/60i | 23.8 | 13.1 | 1639 | 80 | |
| 9. | Pentax KP | APS-C | 24.1 | 6016 | 4000 | 1080/60i | 23.9 | 13.2 | 1699 | 81 | |
| 10. | Pentax K-S1 | APS-C | 20.0 | 5472 | 3648 | 1080/30p | 23.5 | 13.0 | 1061 | 78 | |
| 11. | Pentax K-S2 | APS-C | 20.0 | 5472 | 3648 | 1080/30p | 23.6 | 12.9 | 1514 | 79 | |
| 12. | Sony A1 II | Full Frame | 49.8 | 8640 | 5760 | 8k/30p | 25.4 | 14.8 | 3363 | 97 | |
| 13. | Sony A7 II | Full Frame | 24.0 | 6000 | 4000 | 1080/60p | 24.9 | 13.6 | 2449 | 90 | |
| 14. | Sony A7 III | Full Frame | 24.0 | 6000 | 4000 | 4K/30p | 25.0 | 14.7 | 3730 | 96 | |
| 15. | Sony A9 | Full Frame | 24.0 | 6000 | 4000 | 4K/30p | 24.9 | 13.3 | 3517 | 92 | |
| 16. | Sony A9 II | Full Frame | 24.0 | 6000 | 4000 | 4K/30p | 25.0 | 14.0 | 3434 | 93 | |
| 17. | Sony A77 II | APS-C | 24.0 | 6000 | 4000 | 1080/60p | 24.4 | 13.4 | 1013 | 82 | |
| Note: DXO values in italics represent estimates based on sensor size and age. | |||||||||||
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 III provides a better video resolution than the K-3 II. It can shoot movie footage at 4K/120p, while the Pentax is limited to 1080/60i.
Feature comparison
Beyond body and sensor, cameras can and do differ across a range of features. For example, the A9 III has an electronic viewfinder (9440k 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 III has a higher magnification than the one of the K-3 II (0.9x vs 0.63x), 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 II and Sony A9 III along with similar information for a selection of comparators.

| Camera Model |
Viewfinder (Type or 000 dots) |
Control Panel (yes/no) |
LCD Specifications (inch/000 dots) |
LCD Attach- ment |
Touch Screen (yes/no) |
Max Shutter Speed * |
Max Shutter Flaps * |
Built-in Flash (yes/no) |
Built-in Image Stab |
||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. | Pentax K-3 II | optical | Y | 3.2 / 1037 | fixed | n | 1/8000s | 8.3/s | n | Y | |
| 2. | Sony A9 III | 9440 | n | 3.2 / 2100 | full-flex | Y | 1/80000s | 120.0/s | n | Y | |
| 3. | Nikon D7200 | optical | Y | 3.2 / 1229 | fixed | n | 1/8000s | 6.0/s | Y | n | |
| 4. | Pentax K-3 | optical | Y | 3.2 / 1037 | fixed | n | 1/8000s | 8.3/s | Y | Y | |
| 5. | Pentax K-3 III | optical | Y | 3.2 / 1620 | fixed | Y | 1/8000s | 12.0/s | n | Y | |
| 6. | Pentax K-5 | optical | Y | 3.0 / 921 | fixed | n | 1/8000s | 7.0/s | Y | Y | |
| 7. | Pentax K-5 II | optical | Y | 3.0 / 921 | fixed | n | 1/8000s | 7.0/s | Y | Y | |
| 8. | Pentax K-70 | optical | n | 3.0 / 921 | swivel | n | 1/6000s | 6.0/s | Y | Y | |
| 9. | Pentax KP | optical | n | 3.0 / 921 | tilting | n | 1/6000s | 7.0/s | Y | Y | |
| 10. | Pentax K-S1 | optical | n | 3.0 / 921 | fixed | n | 1/6000s | 5.4/s | Y | Y | |
| 11. | Pentax K-S2 | optical | n | 3.0 / 921 | swivel | n | 1/6000s | 5.4/s | Y | Y | |
| 12. | Sony A1 II | 9437 | n | 3.2 / 2100 | full-flex | Y | 1/8000s | 30.0/s | n | Y | |
| 13. | Sony A7 II | 2400 | n | 3.0 / 1230 | tilting | n | 1/8000s | 5.0/s | n | Y | |
| 14. | Sony A7 III | 2359 | n | 3.0 / 922 | tilting | Y | 1/8000s | 10.0/s | n | Y | |
| 15. | Sony A9 | 3686 | n | 3.0 / 1440 | tilting | Y | 1/8000s | 20.0/s | n | Y | |
| 16. | Sony A9 II | 3686 | n | 3.0 / 1440 | tilting | Y | 1/8000s | 20.0/s | n | Y | |
| 17. | Sony A77 II | 2359 | Y | 3.0 / 1229 | full-flex | n | 1/8000s | 12.0/s | Y | Y | |
| Note: *) Information refers to the mechanical shutter, unless the camera only has an electronic one. | |||||||||||
One feature that is present on the K-3 II, but is missing on the A9 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 A9 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-3 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 A9 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-3 II and the Sony A9 III 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.
The K-3 II writes its imaging data to SDXC cards, while the A9 III uses CFexpress (type A) or SDXC cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails. The A9 III supports UHS-II cards (Ultra High Speed data transfer of up to 312 MB/s), while the K-3 II can use UHS-I cards (up to 104 MB/s).
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 II and Sony Alpha A9 III and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

| 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 II | Y | mono / mono | Y | Y | mini | 3.0 | - | - | - | |
| 2. | Sony A9 III | Y | stereo / mono | Y | Y | full | 3.2 | Y | - | Y | |
| 3. | Nikon D7200 | Y | stereo / mono | Y | Y | mini | 2.0 | Y | Y | - | |
| 4. | Pentax K-3 | Y | mono / mono | Y | Y | mini | 3.0 | - | - | - | |
| 5. | Pentax K-3 III | Y | stereo / mono | Y | Y | micro | 3.2 | Y | - | Y | |
| 6. | Pentax K-5 | Y | stereo / mono | Y | - | mini | 2.0 | - | - | - | |
| 7. | Pentax K-5 II | Y | stereo / mono | Y | - | mini | 2.0 | - | - | - | |
| 8. | Pentax K-70 | Y | stereo / mono | Y | - | mini | 2.0 | Y | - | - | |
| 9. | Pentax KP | Y | stereo / mono | Y | - | - | 2.0 | Y | - | - | |
| 10. | Pentax K-S1 | Y | stereo / mono | - | - | micro | 2.0 | - | - | - | |
| 11. | Pentax K-S2 | Y | mono / mono | Y | - | micro | 2.0 | Y | Y | - | |
| 12. | Sony A1 II | Y | stereo / mono | Y | Y | full | 3.2 | Y | - | Y | |
| 13. | Sony A7 II | Y | stereo / mono | Y | Y | micro | 2.0 | Y | Y | - | |
| 14. | Sony A7 III | Y | stereo / mono | Y | Y | micro | 3.1 | Y | Y | Y | |
| 15. | Sony A9 | Y | stereo / mono | Y | Y | micro | 2.0 | Y | Y | Y | |
| 16. | Sony A9 II | Y | stereo / mono | Y | Y | micro | 3.1 | Y | Y | Y | |
| 17. | Sony A77 II | Y | stereo / mono | Y | - | mini | 2.0 | Y | Y | - |
It is notable that the A9 III 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 provide wifi capability.
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-3 II has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.
The A9 III is a recent model that features in the current product line-up of Sony. In contrast, the K-3 II has been discontinued (but can be found pre-owned on ebay). As a replacement in the same line of cameras, the K-3 II was succeeded by the Pentax K-3 III. Further information on the features and operation of the K-3 II and A9 III can be found, respectively, in the Pentax K-3 II Manual (free pdf) or the online Sony A9 III Manual.
Review summary
So what conclusions can be drawn? Is the Pentax K-3 II better than the Sony A9 III or vice versa? A synthesis of the relative strong points of each of the models is listed below.

Advantages of 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.
- Longer lasting: Can take more shots (720 versus 530) on a single battery charge.
- Easier geotagging: Features an internal GPS sensor to log localization data.
- More affordable: Was introduced into a lower priced category (82 percent cheaper at launch).
- More heavily discounted: Has been available for much longer (launched in April 2015).

Arguments in favor of the Sony Alpha A9 III:
- Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
- Better image quality: Is equipped with a larger and more technologically advanced sensor.
- Richer colors: The sensor size advantage translates into images with better, more accurate colors.
- More dynamic range: Larger sensor captures a wider spectrum of light and dark details.
- Better low-light sensitivity: Larger sensor produces good images even in poorly lit environments.
- Better video: Provides higher definition movie capture (4K/120p 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 (0.9x vs 0.63x).
- More detailed LCD: Has a higher resolution rear screen (2100k vs 1037k dots).
- More flexible LCD: Has a full-flex screen for odd-angle shots in portrait or landscape orientation.
- 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 shutter: Has higher mechanical shutter speed (1/80000s vs 1/8000s) to freeze action.
- Faster burst: Shoots at higher frequency (120 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 98g or 12 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 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 8 years and 6 months of technical progress since the K-3 II launch.
If the count of relative strengths (bullet points above) is taken as a measure, the A9 III is the clear winner of the contest (24 : 8 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.
How about other alternatives? Do the specifications of the Pentax K-3 II and the Sony A9 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 comparison of the spec-sheets of cameras can offer a general idea of their imaging potential, it remains incomplete and does no justice, for example, to the way the K-3 II or the A9 III perform in practice. 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
This is why expert reviews 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.

| Camera Model |
AP score |
CL score |
DCW score |
DPR score |
EPZ score |
PB score |
Camera Launch |
Launch Price |
Street Price |
||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. | Pentax K-3 II | 4.5/5 | .. | .. | .. | 5/5 | 5/5 | Apr 2015 | US$ 1 099 | ebay.com | |
| 2. | Sony A9 III | 4.5/5 | .. | .. | 91/100 | .. | .. | Nov 2023 | US$ 5 999 | amazon.com | |
| 3. | Nikon D7200 | 4/5 | + + | .. | 84/100 | 4.5/5 | 4.5/5 | Mar 2015 | US$ 1 199 | ebay.com | |
| 4. | Pentax K-3 | 4/5 | .. | .. | 83/100 | 5/5 | 5/5 | Oct 2013 | US$ 1 299 | ebay.com | |
| 5. | Pentax K-3 III | 4/5 | .. | 3/5 | .. | 4.5/5 | .. | Mar 2021 | US$ 1 999 | amazon.com | |
| 6. | Pentax K-5 | 4/5 | .. | .. | 83/100 | 5/5 | 4.5/5 | Sep 2010 | US$ 1 099 | ebay.com | |
| 7. | Pentax K-5 II | 5/5 | .. | .. | 80/100 | 5/5 | 4.5/5 | Sep 2012 | US$ 1 099 | ebay.com | |
| 8. | Pentax K-70 | 4.5/5 | .. | 4/5 | 79/100 | 4.5/5 | 4.5/5 | Jun 2016 | US$ 649 | ebay.com | |
| 9. | Pentax KP | 4/5 | .. | 3/5 | 82/100 | 5/5 | 4.5/5 | Jan 2017 | US$ 1 099 | ebay.com | |
| 10. | Pentax K-S1 | 4/5 | .. | .. | .. | 4.5/5 | 4/5 | Aug 2014 | US$ 749 | ebay.com | |
| 11. | Pentax K-S2 | 4.5/5 | .. | .. | .. | 5/5 | 4.5/5 | Feb 2015 | US$ 749 | ebay.com | |
| 12. | Sony A1 II | .. | .. | .. | .. | .. | .. | Nov 2024 | US$ 6 499 | amazon.com | |
| 13. | Sony A7 II | 5/5 | + | 4/5 | 82/100 | 4.5/5 | 5/5 | Nov 2014 | US$ 1 999 | ebay.com | |
| 14. | Sony A7 III | .. | + + | 4.5/5 | 89/100 | 5/5 | 5/5 | Feb 2018 | US$ 1 999 | amazon.com | |
| 15. | Sony A9 | 5/5 | + + | 4.8/5 | 89/100 | 5/5 | 5/5 | Apr 2017 | US$ 4 499 | ebay.com | |
| 16. | Sony A9 II | .. | .. | 5/5 | 90/100 | 5/5 | 5/5 | Oct 2019 | US$ 4 499 | amazon.com | |
| 17. | Sony A77 II | 4/5 | .. | .. | 80/100 | 4.5/5 | 5/5 | May 2014 | US$ 1 199 | ebay.com | |
| Note: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available. | |||||||||||
The above review scores should be interpreted with care, though. The assessments were made in relation to similar cameras of the same technological generation. A score, therefore, has to be seen in close connection to the price and market introduction time 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. It should also be noted that some of the review sites have over time altered the way they render their verdicts.

Check K-3 II offers at
ebay.com

Check A9 III price at
amazon.com
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 1100D vs Sony A9 III
- Fujifilm X-H1 vs Sony A9 III
- Leica D-LUX 6 vs Sony A9 III
- Leica M10-P vs Pentax K-3 II
- Nikon 1 J4 vs Pentax K-3 II
- Nikon D40X vs Pentax K-3 II
- Nikon D5500 vs Pentax K-3 II
- Nikon D610 vs Pentax K-3 II
- Panasonic G7 vs Sony A9 III
- Panasonic GH3 vs Pentax K-3 II
- Ricoh WG-60 vs Sony A9 III
- Sony A7R IV vs Sony A9 III
Specifications: Pentax K-3 II vs Sony A9 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-3 II | Sony A9 III |
|---|---|---|
| Camera Type | Digital single lens reflex | Mirrorless system camera |
| Camera Lens | Pentax K mount lenses | Sony E mount lenses |
| Launch Date | April 2015 | November 2023 |
| Launch Price | USD 1,099 | USD 5,999 |
| Sensor Specs | Pentax K-3 II | Sony A9 III |
| Sensor Technology | CMOS | Stacked CMOS |
| 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 |
| Crop Factor | 1.5x | 1.0x |
| 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/120p Video |
| ISO Setting | 100 - 51,200 ISO | 250 - 25,600 ISO |
| ISO Boost | no Enhancement | 125 - 51,200 ISO |
| Image Processor | PRIME III | Dual BIONZ XR |
| DXO Sensor Quality (score) | 80 | .. |
| DXO Color Depth (bits) | 23.6 | .. |
| DXO Dynamic Range (EV) | 13.6 | .. |
| DXO Low Light (ISO) | 1106 | .. |
| Screen Specs | Pentax K-3 II | Sony A9 III |
| Viewfinder Type | Optical viewfinder | Electronic viewfinder |
| Viewfinder Field of View | 100% | 100% |
| Viewfinder Magnification | 0.63x | 0.9x |
| Viewfinder Resolution | 9440k dots | |
| Top-Level Screen | Control Panel | no Top Display |
| LCD Framing | Live View | Live View |
| Rear LCD Size | 3.2inch | 3.2inch |
| LCD Resolution | 1037k dots | 2100k dots |
| LCD Attachment | Fixed screen | Fully flexible screen |
| Touch Input | no Touchscreen | Touchscreen |
| Shooting Specs | Pentax K-3 II | Sony A9 III |
| Focus System | Phase-detect AF | On-Sensor Phase-detect |
| Manual Focusing Aid | Focus Peaking | Focus Peaking |
| Max Shutter Speed (mechanical) | 1/8000s | 1/80000s |
| Continuous Shooting | 8.3 shutter flaps/s | 120 shutter flaps/s |
| Electronic Shutter | no E-Shutter | up to 1/80000s |
| 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 | CFexA or SDXC cards |
| Single or Dual Card Slots | Dual card slots | Dual card slots |
| UHS card support | UHS-I | UHS-II |
| Connectivity Specs | Pentax K-3 II | Sony A9 III |
| External Flash | Hotshoe | Hotshoe |
| Studio Flash | PC Sync socket | PC Sync socket |
| USB Connector | USB 3.0 | USB 3.2 |
| HDMI Port | mini HDMI | full HDMI |
| Microphone Port | External MIC port | External MIC port |
| Headphone Socket | Headphone port | Headphone port |
| Wifi Support | no Wifi | Wifi built-in |
| Bluetooth Support | no Bluetooth | Bluetooth built-in |
| Geotagging | GPS built-in | no internal GPS |
| Body Specs | Pentax K-3 II | Sony A9 III |
| Environmental Sealing | Weathersealed body | Weathersealed body |
| Battery Type | Pentax D-LI90 | Sony NP-FZ100 |
| Battery Life (CIPA) | 720 shots per charge | 530 shots per charge |
| In-Camera Charging | no USB charging | USB charging |
| Body Dimensions |
131 x 100 x 77 mm (5.2 x 3.9 x 3.0 in) |
136 x 97 x 83 mm (5.4 x 3.8 x 3.3 in) |
| Camera Weight | 800 g (28.2 oz) | 702 g (24.8 oz) |

Check K-3 II offers at
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Check A9 III price at
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