Panasonic GX9 vs Pentax K-3 II
The Panasonic Lumix DC-GX9 and the Pentax K-3 II are two enthusiast cameras that were revealed to the public, respectively, in February 2018 and April 2015. The GX9 is a mirrorless interchangeable lens camera, while the K-3 II is a DSLR. The cameras are based on a Four Thirds (GX9) and an APS-C (K-3 II) sensor. The Panasonic has a resolution of 20.2 megapixels, whereas the Pentax provides 24.1 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 Panasonic Lumix DC-GX9 and the Pentax K-3 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 Panasonic GX9 and the Pentax K-3 II 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 measures are rounded to the nearest millimeter.
Both cameras are available in two different colors (black, silver).
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 is considerably larger (47 percent) than the Panasonic GX9. Moreover, the K-3 II is substantially heavier (97 percent) than the GX9. It is noteworthy in this context that the K-3 II is splash and dust-proof, while the GX9 does not feature any corresponding weather-sealing.
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 GX9 gets 260 shots out of its DMW-BLG10 battery, while the K-3 II can take 720 images on a single charge of its D-LI90 power pack. The power pack in the GX9 can be charged via the USB port, so that it is not always necessary to take the battery charger along when travelling.
The adjacent table lists the principal physical characteristics of the two cameras alongside a wider set of alternatives. 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.
|Panasonic GX9||4.9 in||2.8 in||1.9 in||14.4 oz||260||n||Feb 2018||849|
|Pentax K-3 II||5.2 in||3.9 in||3.0 in||28.2 oz||720||Y||Apr 2015||1,099|
|Canon 80D||5.5 in||4.1 in||3.1 in||25.8 oz||960||Y||Feb 2016||1,199|
|Olympus E-M10 IV||4.8 in||3.3 in||1.9 in||13.5 oz||360||n||Aug 2020||699|
|Olympus E-M10 III||4.8 in||3.3 in||2.0 in||14.5 oz||330||n||Aug 2017||649|
|Olympus PEN-F||4.9 in||2.8 in||1.5 in||15.1 oz||330||n||Jan 2016||1,199|
|Olympus E-M10 II||4.7 in||3.3 in||1.9 in||13.8 oz||320||n||Aug 2015||649|
|Panasonic G95||5.1 in||3.7 in||3.0 in||18.9 oz||290||Y||Apr 2019||999|
|Panasonic LX100 II||4.5 in||2.6 in||2.6 in||13.8 oz||300||n||Aug 2018||999|
|Panasonic ZS200||4.4 in||2.6 in||1.8 in||12.0 oz||370||n||Feb 2018||799|
|Panasonic GX85||4.8 in||2.8 in||1.7 in||15.0 oz||290||n||Apr 2016||799|
|Panasonic GX8||5.2 in||3.1 in||2.5 in||17.2 oz||330||Y||Jul 2015||1,199|
|Panasonic GX7||4.8 in||2.8 in||2.2 in||14.2 oz||350||n||Aug 2013||999|
|Pentax KP||5.2 in||4.0 in||3.0 in||24.8 oz||390||Y||Jan 2017||1,099|
|Pentax K-70||5.0 in||3.7 in||2.9 in||24.3 oz||410||Y||Jun 2016||649|
|Pentax K-3||5.2 in||3.9 in||3.0 in||28.2 oz||560||Y||Oct 2013||1,299|
|Pentax K-5||5.2 in||3.8 in||2.9 in||26.8 oz||740||Y||Sep 2010||1,099|
|Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.|
The price is, of course, an important factor in any camera decision. The 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 GX9 was launched at a somewhat lower price (by 23 percent) than the K-3 II, which makes it more attractive for photographers on a tight budget. 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.
The imaging sensor is at the core of digital cameras and its size is one of the main determining factors of image quality. A large sensor will tend to have larger individual pixels that provide better low-light sensitivity, wider dynamic range, and richer color-depth than smaller pixel-units in a sensor of the same technological generation. Furthermore, a large sensor camera will give the photographer more possibilities to use shallow depth-of-field in order to isolate a subject from the background. On the downside, larger sensors tend to be more expensive and lead to bigger and heavier cameras and lenses.
Of the two cameras under consideration, the Panasonic GX9 features a Four Thirds sensor and the Pentax K-3 II an APS-C sensor. The sensor area in the K-3 II is 63 percent bigger. As a result of these sensor size differences, the cameras have a format factor of, respectively, 2.0 and 1.5. The sensor in the GX9 has a native 4:3 aspect ratio, while the one in the K-3 II offers a 3:2 aspect.
In terms of underlying technology, both cameras are build around CMOS sensors.
With 24.1MP, the K-3 II offers a higher resolution than the GX9 (20.2MP), but the K-3 II nevertheless has larger individual pixels (pixel pitch of 3.90μm versus 3.34μm for the GX9) due to its larger sensor. However, the GX9 is a much more recent model (by 2 years and 9 months) than the K-3 II, and its sensor will have benefitted from technological advances during this time that enhance the light gathering capacity of its pixel-units. Coming back to sensor resolution, it should be mentioned that neither of the two cameras has an anti-alias filter installed, so they are able to capture all the detail the sensor resolves.
The resolution advantage of the Pentax K-3 II implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the K-3 II for good quality output (200 dots per inch) amounts to 30.1 x 20 inches or 76.4 x 50.8 cm, for very good quality (250 dpi) 24.1 x 16 inches or 61.1 x 40.6 cm, and for excellent quality (300 dpi) 20.1 x 13.3 inches or 50.9 x 33.9 cm. The corresponding values for the Panasonic GX9 are 25.9 x 19.4 inches or 65.8 x 49.4 cm for good quality, 20.7 x 15.6 inches or 52.7 x 39.5 cm for very good quality, and 17.3 x 13 inches or 43.9 x 32.9 cm for excellent quality prints.
Unlike the GX9, 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 Panasonic Lumix DC-GX9 has a native sensitivity range from ISO 200 to ISO 25600, which can be extended to ISO 100-25600. The corresponding ISO settings for the Pentax K-3 II are ISO 100 to ISO 51200 (no boost).
Since 2007, DXO Mark has published sensor performance measurements that have been derived using a consistent methodology. 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 adjacent table reports on the physical sensor characteristics and the outcomes of the DXO sensor quality tests for a sample of comparator-cameras.
| DXO |
|Panasonic GX9||Four Thirds||20.2||5184||3888||4K/30p||..||..||..||..|
|Pentax K-3 II||APS-C||24.1||6016||4000||1080/60i||23.6||13.6||1106||80|
|Olympus E-M10 IV||Four Thirds||20.2||5184||3888||4K/30p||..||..||..||..|
|Olympus E-M10 III||Four Thirds||15.9||4608||3456||4K/30p||..||..||..||..|
|Olympus PEN-F||Four Thirds||20.2||5184||3888||1080/60p||23.1||12.4||894||74|
|Olympus E-M10 II||Four Thirds||15.9||4608||3456||1080/60p||23.1||12.5||842||73|
|Panasonic G95||Four Thirds||20.2||5184||3888||4K/30p||..||..||..||..|
|Panasonic LX100 II||Four Thirds||16.8||4736||3552||4K/30p||..||..||..||..|
|Panasonic GX85||Four Thirds||15.8||4592||3448||4K/30p||22.9||12.6||662||71|
|Panasonic GX8||Four Thirds||20.2||5184||3888||4K/30p||23.5||12.6||806||75|
|Panasonic GX7||Four Thirds||15.8||4592||3448||1080/60p||22.6||12.2||718||70|
Many modern cameras cannot only take still pictures, but also record videos. The two cameras under consideration both have sensors whose read-out speed is fast enough to capture moving pictures, but the GX9 provides a higher video resolution than the K-3 II. It can shoot video footage at 4K/30p, 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 GX9 has an electronic viewfinder (2760k 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 GX9 has a higher magnification than the one of the K-3 II (0.70x vs 0.63x), 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 Panasonic GX9 and Pentax K-3 II in connection with corresponding information for a sample of similar cameras.
|Pentax K-3 II||optical||Y||3.2||1037||fixed||n||1/8000s||8.3||n||Y|
|Olympus E-M10 IV||2360||n||3.0||1040||tilting||Y||1/4000s||15.0||Y||Y|
|Olympus E-M10 III||2360||n||3.0||1040||tilting||Y||1/4000s||8.6||Y||Y|
|Olympus E-M10 II||2360||n||3.0||1040||tilting||Y||1/4000s||8.0||Y||Y|
|Panasonic LX100 II||2764||n||3.0||1240||fixed||Y||1/4000s||11.0||n||Y|
One difference between the cameras concerns the presence of an on-board flash. The GX9 has one, while the K-3 II does not. While the built-in flash of the GX9 is not very powerful, it can at times be useful as a fill-in light.
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 GX9 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 Panasonic GX9 and the Pentax K-3 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 GX9 and the K-3 II write their files to SDXC cards. The K-3 II features dual card slots, which can be very useful in case a memory card fails. In contrast, the GX9 only has one slot. Both cameras can use UHS-I cards, which provide for Ultra High Speed data transfer of up to 104 MB/s.
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 Panasonic Lumix DC-GX9 and Pentax K-3 II and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
| NFC |
|Pentax K-3 II||Y||mono||mono||Y||Y||mini||3.0||-||-||-|
|Olympus E-M10 IV||Y||stereo||mono||-||-||micro||2.0||Y||-||Y|
|Olympus E-M10 III||Y||stereo||mono||-||-||micro||2.0||Y||-||-|
|Olympus E-M10 II||Y||stereo||mono||-||-||micro||2.0||Y||-||-|
|Panasonic LX100 II||Y||stereo||mono||-||-||micro||2.0||Y||-||Y|
It is notable that the GX9 offers wifi support, while the K-3 II does not. Wifi can be a very convenient means to transfer image data to an off-camera location.
Studio photographers will appreciate that the Pentax K-3 II (unlike the GX9) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
Travel and landscape photographers will find it useful that the K-3 II has an internal geolocalization sensor and can record GPS coordinates in its EXIF data.
Both the GX9 and the K-3 II are recent models that are part of the current product line-up. The K-3 II replaced the earlier Pentax K-3, while the GX9 followed on from the Panasonic GX8. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Panasonic and Pentax websites.
So what conclusions can be drawn? Is the Panasonic GX9 better than the Pentax K-3 II or vice versa? The listing below highlights the relative strengths of the two models.
Reasons to prefer the Panasonic Lumix DC-GX9:
- Better video: Provides higher definition movie capture (4K/30p vs 1080/60i).
- More framing info: Has an electronic viewfinder that displays shooting data.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.70x vs 0.63x).
- More detailed LCD: Has a higher resolution rear screen (1240k vs 1037k dots).
- More flexible LCD: Has a tilting screen for odd-angle shots in landscape orientation.
- Fewer buttons to press: Is equipped with a touch-sensitive rear screen to facilitate handling.
- Less disturbing: Has an electronic shutter option for completely silent shooting.
- More compact: Is smaller (124x72mm vs 131x100mm) and thus needs less room in the bag.
- Less heavy: Is lighter (by 393g or 49 percent) and hence easier to carry around.
- Easier travel charging: Can be conveniently charged via its USB port.
- More legacy lens friendly: Can take a broad range of non-native lenses via adapters.
- Easier fill-in: Is equipped with a small onboard flash to brighten deep shadow areas.
- 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.
- More affordable: Was introduced into a lower priced segment (23 percent cheaper at launch).
- More modern: Reflects 2 years and 9 months of technical progress since the K-3 II launch.
Advantages of the Pentax K-3 II:
- More detail: Has more megapixels (24.1 vs 20.2MP), which boosts linear resolution by 11%.
- High quality composites: Can combine several shots after pixel-shifting its sensor.
- Better image quality: Features bigger pixels on a larger sensor for higher quality imaging.
- Richer colors: The pixel size advantage translates into images with better, more accurate colors.
- More dynamic range: Larger pixels capture a wider spectrum of light and dark details.
- Better low-light sensitivity: Larger pixels means good image quality even under poor lighting.
- Better sound: Can connect to an external microphone for higher quality sound recording.
- Better sound control: Has a headphone port that enables audio monitoring while recording.
- Brighter framing: Features an optical viewfinder for clear, lag-free composition.
- Easier setting verification: Features a control panel on top to check shooting parameters.
- Larger screen: Has a bigger rear LCD (3.2" vs 3.0") for image review and settings control.
- Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
- Longer lasting: Gets more shots (720 versus 260) out of a single battery charge.
- Better sealing: Is splash and dust sealed for shooting in inclement weather conditions.
- Easier geotagging: Features an internal GPS sensor to log localization data.
- 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.
- Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
- More heavily discounted: Has been around for much longer (launched in April 2015).
If the count of individual advantages (bullet points above) is taken as a guide, the K-3 II emerges as the winner of the match-up (19 : 16 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 wildlife photographer will view the differences between cameras in a way that diverges from the perspective of a family photog, and a person interested in architecture has distinct needs from a sports 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 Panasonic GX9 and the Pentax K-3 II place the cameras among the top in their class? Find out in the latest Best Mirrorless Interchangeable Lens Camera and Best DSLR 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 partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the GX9 or the K-3 II. 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 hands-on reviews by experts are important. 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.
|Panasonic GX9||+||84/100||4.5/5||4.5/5||4.5/5||Feb 2018||849|
|Pentax K-3 II||..||..||5/5||4.5/5||5/5||Apr 2015||1,099|
|Canon 80D||+ +||84/100||4.5/5||4.5/5||4.5/5||Feb 2016||1,199|
|Olympus E-M10 IV||..||..||4.5/5||..||4.5/5||Aug 2020||699|
|Olympus E-M10 III||+||80/100||4.5/5||4/5||4.5/5||Aug 2017||649|
|Olympus PEN-F||..||82/100||4.5/5||4.5/5||5/5||Jan 2016||1,199|
|Olympus E-M10 II||+ +||80/100||5/5||5/5||5/5||Aug 2015||649|
|Panasonic G95||+||83/100||4.5/5||4.5/5||4.5/5||Apr 2019||999|
|Panasonic LX100 II||+||82/100||4.5/5||4.5/5||4.5/5||Aug 2018||999|
|Panasonic ZS200||+ +||81/100||4.5/5||..||4.5/5||Feb 2018||799|
|Panasonic GX85||+ +||82/100||5/5||4.5/5||5/5||Apr 2016||799|
|Panasonic GX8||+||82/100||4.5/5||5/5||4.5/5||Jul 2015||1,199|
|Panasonic GX7||+||79/100||5/5||4.5/5||5/5||Aug 2013||999|
|Pentax KP||..||82/100||5/5||..||4.5/5||Jan 2017||1,099|
|Pentax K-70||..||79/100||4.5/5||4/5||4.5/5||Jun 2016||649|
|Pentax K-3||..||83/100||5/5||4.5/5||5/5||Oct 2013||1,299|
|Pentax K-5||..||83/100||5/5||4.5/5||4.5/5||Sep 2010||1,099|
|Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.|
Care should be taken when interpreting the review scores above, though. The ratings are only valid when referring to cameras in the same category and of the same age. Hence, a score should always be seen in the context of the camera's market launch date and its price, and rating-comparisons among cameras that span long time periods or concern very differently equipped models make little sense. It should also be noted that some of the review sites have over time altered the way they render their verdicts.
Other camera comparisons
Did this review help to inform your camera decision process? If you would like to see a different side-by-side camera review, just make a corresponding selection in the search boxes below. 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: Panasonic GX9 vs Pentax K-3 II
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||Panasonic GX9||Pentax K-3 II|
|Camera Type||Mirrorless system camera||Digital single lens reflex|
|Camera Lens||Micro Four Thirds lenses||Pentax K mount lenses|
|Launch Date||February 2018||April 2015|
|Launch Price||USD 849||USD 1,099|
|Sensor Specs||Panasonic GX9||Pentax K-3 II|
|Sensor Format||Four Thirds Sensor||APS-C Sensor|
|Sensor Size||17.3 x 13.0 mm||23.5 x 15.6 mm|
|Sensor Area||224.9 mm2||366.6 mm2|
|Sensor Diagonal||21.6 mm||28.2 mm|
|Sensor Resolution||20.2 Megapixels||24.1 Megapixels|
|Image Resolution||5184 x 3888 pixels||6016 x 4000 pixels|
|Pixel Pitch||3.34 μm||3.90 μm|
|Pixel Density||8.96 MP/cm2||6.56 MP/cm2|
|Moiré control||no AA filter||no AA filter|
|Movie Capability||4K/30p Video||1080/60i Video|
|ISO Setting||200 - 25,600 ISO||100 - 51,200 ISO|
|ISO Boost||100 - 25,600 ISO||no Enhancement|
|Image Processor||Venus||PRIME III|
|DXO Sensor Quality (score)||..||80|
|DXO Color Depth (bits)||..||23.6|
|DXO Dynamic Range (EV)||..||13.6|
|DXO Low Light (ISO)||..||1106|
|Screen Specs||Panasonic GX9||Pentax K-3 II|
|Viewfinder Type||Electronic viewfinder||Optical viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||2760k dots|
|Top-Level Screen||no Top Display||Control Panel|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.0inch||3.2inch|
|LCD Resolution||1240k dots||1037k dots|
|LCD Attachment||Tilting screen||Fixed screen|
|Touch Input||Touchscreen||no Touchscreen|
|Shooting Specs||Panasonic GX9||Pentax K-3 II|
|Focus System||Contrast-detect AF||Phase-detect AF|
|Manual Focusing Aid||Focus Peaking||Focus Peaking|
|Max Shutter Speed (mechanical)||1/4000s||1/8000s|
|Continuous Shooting||9 shutter flaps/s||8.3 shutter flaps/s|
|Electronic Shutter||up to 1/16000s||no E-Shutter|
|Time-Lapse Photography||Intervalometer built-in||Intervalometer built-in|
|Image Stabilization||In-body stabilization||In-body stabilization|
|Fill Flash||Build-in Flash||no On-Board Flash|
|Storage Medium||SDXC cards||SDXC cards|
|Second Storage Option||Single card slot||Dual card slots|
|UHS card support||UHS-I||UHS-I|
|Connectivity Specs||Panasonic GX9||Pentax K-3 II|
|Studio Flash||no PC Sync||PC Sync socket|
|USB Connector||USB 2.0||USB 3.0|
|HDMI Port||micro HDMI||mini HDMI|
|Microphone Port||no MIC socket||External MIC port|
|Headphone Socket||no Headphone port||Headphone port|
|Wifi Support||Wifi built-in||no Wifi|
|Bluetooth Support||Bluetooth built-in||no Bluetooth|
|Geotagging||no internal GPS||GPS built-in|
|Body Specs||Panasonic GX9||Pentax K-3 II|
|Environmental Sealing||not weather sealed||Weathersealed body|
|Battery Life (CIPA)||260 shots per charge||720 shots per charge|
|In-Camera Charging||USB charging||no USB charging|
124 x 72 x 47 mm
(4.9 x 2.8 x 1.9 in)
131 x 100 x 77 mm
(5.2 x 3.9 x 3.0 in)
|Camera Weight||407 g (14.4 oz)||800 g (28.2 oz)|
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