Pentax 645Z vs Sony RX10
The Pentax 645Z and the Sony Cyber-shot DSC-RX10 are two digital cameras that were officially introduced, respectively, in April 2014 and October 2013. The 645Z is a DSLR, while the RX10 is a fixed lens compact. The cameras are based on a medium format (645Z) and an one-inch (RX10) sensor. The Pentax has a resolution of 51.1 megapixels, whereas the Sony provides 20 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 645Z and the Sony Cyber-shot DSC-RX10? 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 side-by-side display below illustrates the physical size and weight of the Pentax 645Z and the Sony RX10. The two cameras are presented according to their relative size. Three successive views from the front, the top, and the rear are shown. All size dimensions are rounded to the nearest millimeter.
If the front view area (width x height) of the cameras is taken as an aggregate measure of their size, the Sony RX10 is considerably smaller (38 percent) than the Pentax 645Z. 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 and possibly misleading, as the RX10 has a lens built in, whereas the 645Z is an interchangeable lens camera that requires a separate lens. Attaching the latter will add extra weight and bulk to the setup.
Concerning battery life, the 645Z gets 650 shots out of its D-LI90 battery, while the RX10 can take 420 images on a single charge of its NP-FW50 power pack. The power pack in the RX10 can be charged via the USB port, which can be very convenient when travelling.
The table below summarizes the key physical specs of the two cameras alongside a broader set of comparators. 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 645Z||156 mm||117 mm||123 mm||1550 g||650||Y||Apr 2014||8,499|
|2.||Sony RX10||129 mm||88 mm||102 mm||813 g||420||Y||Oct 2013||1,299|
|3.||Canon 1D X Mark II||158 mm||168 mm||83 mm||1530 g||1210||Y||Feb 2016||5,999|
|4.||Canon 5DS||152 mm||116 mm||76 mm||930 g||700||Y||Feb 2015||3,699|
|5.||Canon 5DS R||152 mm||116 mm||76 mm||930 g||700||Y||Feb 2015||3,699|
|6.||Canon G3 X||123 mm||77 mm||105 mm||733 g||300||Y||Jun 2015||999|
|7.||Canon 70D||139 mm||104 mm||79 mm||755 g||920||Y||Jul 2013||1,199|
|8.||Hasselblad X1D||150 mm||98 mm||71 mm||725 g||..||Y||Jun 2016||8,995|
|9.||Leica SL||147 mm||104 mm||39 mm||847 g||400||Y||Oct 2015||7,450|
|10.||Nikon D850||146 mm||124 mm||79 mm||1005 g||1840||Y||Jul 2017||3,299|
|11.||Nikon D5||160 mm||159 mm||92 mm||1415 g||3780||Y||Jan 2016||6,499|
|12.||Nikon D7200||136 mm||107 mm||76 mm||765 g||1110||Y||Mar 2015||1,199|
|13.||Nikon D4S||160 mm||157 mm||91 mm||1350 g||3020||Y||Feb 2014||6,499|
|14.||Nikon D7100||136 mm||107 mm||76 mm||765 g||950||Y||Feb 2013||1,199|
|15.||Panasonic FZ1000||137 mm||99 mm||131 mm||831 g||360||n||Jun 2014||899|
|16.||Pentax 645D||156 mm||117 mm||119 mm||1480 g||800||Y||Mar 2010||9,995|
|17.||Sony RX10 II||129 mm||88 mm||102 mm||813 g||400||Y||Jun 2015||1,299|
|Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.|
Any camera decision will naturally be influenced heavily by the price. 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 RX10 was launched at a lower price than the 645Z, despite having a lens built in. Usually, retail prices stay at first close to the launch price, but after several months, discounts become available. Later in the product cycle and, in particular, when the replacement model is about to appear, further discounting and stock clearance sales often push the camera price considerably down.
The size of the imaging sensor is a crucial determinant 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. 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 are more costly to manufacture and tend to lead to bigger and heavier cameras and lenses.
Of the two cameras under consideration, the Pentax 645Z features a medium format sensor and the Sony RX10 an one-inch sensor. The sensor area in the RX10 is 92 percent smaller. As a result of these sensor size differences, the cameras have a format factor of, respectively, 0.79 and 2.7. The sensor in the 645Z has a native 4:3 aspect ratio, while the one in the RX10 offers a 3:2 aspect.
With 51.1MP, the 645Z offers a higher resolution than the RX10 (20MP), but the 645Z nevertheless has larger individual pixels (pixel pitch of 5.30μm versus 2.41μm for the RX10) due to its larger sensor. Moreover, the 645Z is a somewhat more recent model (by 5 months) than the RX10, 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 645Z has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.
The resolution advantage of the Pentax 645Z implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the 645Z for good quality output (200 dots per inch) amounts to 41.3 x 31 inches or 104.9 x 78.6 cm, for very good quality (250 dpi) 33 x 24.8 inches or 83.9 x 62.9 cm, and for excellent quality (300 dpi) 27.5 x 20.6 inches or 69.9 x 52.4 cm. The corresponding values for the Sony RX10 are 27.4 x 18.2 inches or 69.5 x 46.3 cm for good quality, 21.9 x 14.6 inches or 55.6 x 37.1 cm for very good quality, and 18.2 x 12.2 inches or 46.3 x 30.9 cm for excellent quality prints.
The Pentax 645Z has a native sensitivity range from ISO 100 to ISO 204800. The corresponding ISO settings for the Sony Cyber-shot DSC-RX10 are ISO 125 to ISO 12800, with the possibility to increase the ISO range to 80-25600.
Consistent information on actual sensor performance is available from DXO Mark for many cameras. This service determines an overall sensor rating, as well as sub-scores for low-light sensitivity ("DXO Sports"), dynamic range ("DXO Landscape"), and color depth ("DXO Portrait"). Of the two cameras under review, the 645Z provides substantially higher image quality than the RX10, with an overall score that is 32 points higher. This advantage is based on 3.1 bits higher color depth, 2.1 EV in additional dynamic range, and 3.2 stops in additional low light sensitivity. 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 645Z||Medium Format||51.1||8256||6192||1080/60i||26.0||14.7||4505||101|
|3.||Canon 1D X Mark II||Full Frame||20.0||5472||3648||4K/60p||24.1||13.5||3207||88|
|4.||Canon 5DS||Full Frame||50.3||8688||5792||1080/30p||24.7||12.4||2381||87|
|5.||Canon 5DS R||Full Frame||50.3||8688||5792||1080/30p||24.6||12.4||2308||86|
|6.||Canon G3 X||1-inch||20.0||5472||3648||1080/60p||21.4||12.3||521||63|
|8.||Hasselblad X1D||Medium Format||51.3||8272||6200||1080/25p||26.2||14.8||4489||102|
|9.||Leica SL||Full Frame||24.0||6000||4000||4K/30p||25.0||13.4||1821||88|
|10.||Nikon D850||Full Frame||45.4||8256||5504||4K/30p||26.4||14.8||2660||100|
|11.||Nikon D5||Full Frame||20.7||5588||3712||4K/30p||25.1||12.3||2343||88|
|13.||Nikon D4S||Full Frame||16.2||4928||3280||1080/60p||24.4||13.3||3074||89|
|16.||Pentax 645D||Medium Format||39.5||7264||5440||none||24.6||12.6||1262||82|
|17.||Sony RX10 II||1-inch||20.0||5472||3648||4K/30p||23.0||12.6||531||70|
Many modern cameras are not only capable of taking still images, but can also record movies. Both cameras under consideration have a sensor with sufficiently fast read-out times for moving pictures, but the RX10 provides a faster frame rate than the 645Z. It can shoot movie footage at 1080/60p, 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 RX10 has an electronic viewfinder (1440k dots), while the 645Z 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 viewfinder in the RX10 offers a wider field of view (100%) than the one in the 645Z (98%), so that a larger proportion of the captured image is visible in the finder. On the other hand, the viewfinder of the 645Z has a higher magnification (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 adjacent table lists some of the other core features of the Pentax 645Z and Sony RX10 along with similar information for a selection of comparators.
|3.||Canon 1D X Mark II||optical||Y||3.2||1620||fixed||Y||1/8000s||16.0||n||n|
|5.||Canon 5DS R||optical||Y||3.2||1040||fixed||n||1/8000s||5.0||n||n|
|6.||Canon G3 X||optional||n||3.2||1620||tilting||Y||1/2000s||5.9||Y||Y|
|17.||Sony RX10 II||2359||Y||3.0||1229||tilting||n||1/3200s||14.0||Y||Y|
One difference between the cameras concerns the presence of an on-board flash. The RX10 has one, while the 645Z does not. While the built-in flash of the RX10 is not very powerful, it can at times be useful as a fill-in light.
The Pentax 645Z 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 645Z writes its imaging data to SDXC cards, while the RX10 uses SDXC or Memory Stick PRO Duo cards. The 645Z features dual card slots, which can be very useful in case a memory card fails. In contrast, the RX10 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 Pentax 645Z and Sony Cyber-shot DSC-RX10 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
| NFC |
|3.||Canon 1D X Mark II||Y||mono||mono||Y||Y||mini||3.0||-||-||-|
|5.||Canon 5DS R||Y||mono||mono||Y||-||mini||3.0||-||-||-|
|6.||Canon G3 X||Y||stereo||mono||Y||Y||mini||2.0||Y||Y||-|
|17.||Sony RX10 II||Y||stereo||mono||Y||Y||micro||2.0||Y||Y||-|
It is notable that the RX10 offers wifi support, which can be a very convenient means to transfer image data to an off-camera location. In contrast, the 645Z does not provide wifi capability.
Studio photographers will appreciate that the Pentax 645Z (unlike the RX10) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
The 645Z is a recent model that features in the current product line-up of Pentax. In contrast, the RX10 has been discontinued (but can be found pre-owned on eBay). As a replacement in the same line of cameras, the RX10 was succeeded by the Sony RX10 II. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Pentax and Sony websites.
So what conclusions can be drawn? Is there a clear favorite between the Pentax 645Z and the Sony RX10? Which camera is better? Below is a summary of the relative strengths of each of the two contestants.
Advantages of the Pentax 645Z:
- More detail: Offers more megapixels (51.1 vs 20MP) with a 57% higher linear resolution.
- Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
- Better image quality: Scores substantially higher (32 points) in the DXO overall assessment.
- Richer colors: Generates images with noticeably better colors (3.1 bits more color depth).
- More dynamic range: Captures a larger spectrum of light and dark details (2.1 EV of extra DR).
- Better low-light sensitivity: Requires less light for good images (3.2 stops ISO advantage).
- Brighter framing: Features an optical viewfinder for clear, lag-free composition.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.78x vs 0.70x).
- 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 (1/4000s vs 1/3200s) to freeze action.
- Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
- More flexible: Can take a variety of interchangeable lenses, including specialty optics.
- Longer lasting: Can take more shots (650 versus 420) 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.
- Greater peace of mind: Features a second card slot as a backup in case of memory card failure.
- More modern: Is somewhat more recent (announced 5 months after the RX10).
Arguments in favor of the Sony Cyber-shot DSC-RX10:
- Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
- Better video: Provides higher movie framerates (1080/60p versus 1080/60i).
- Better sound control: Has a headphone port that enables audio monitoring while recording.
- More framing info: Has an electronic viewfinder that displays shooting data.
- More complete view: Has a viewfinder with a larger field of view (100% vs 98%).
- More detailed LCD: Has a higher resolution rear screen (1229k vs 1037k dots).
- Faster burst: Shoots at higher frequency (10 vs 3 flaps/sec) to capture the decisive moment.
- Ready to shoot: Comes with an integrated lens, while the 645Z requires a separate lens.
- More compact: Is smaller (129x88mm vs 156x117mm) and will fit more readily into a bag.
- Less heavy: Has a lower weight even though it has a lens built in (unlike the 645Z).
- Easier travel charging: Can be conveniently charged via its USB port.
- Sharper images: Has stabilization technology built-in to reduce the impact of hand-shake.
- Easier fill-in: Has a small integrated flash to brighten shadows of backlit subjects.
- 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.
- More affordable: Was introduced at a lower price, despite coming with a built-in lens.
- More heavily discounted: Has been on the market for longer (launched in October 2013).
If the number of relative strengths (bullet points above) is taken as a guide, the match-up finishes in a tie (17 points each). 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 Pentax 645Z and the Sony RX10 place the cameras among the top in their class? Find out in the latest Best DSLR Camera and Best Travel-Zoom Camera listings whether the two cameras rank among the cream of the crop.
In any case, while the comparison of technical specifications can provide a useful overview of the capabilities of different cameras, it remains partial and cannot reveal, for example, the shooting experience and imaging performance when actually working with the 645Z or the RX10. User reviews that are available, for instance, at amazon can sometimes shed light on these issues, but such feedback is all too often partial, inconsistent, and inaccurate.
This is where reviews by experts come in. The adjacent summary-table relays the overall verdicts of several of the most popular camera review sites (amateurphotographer [AP], cameralabs [CL], dpreview [DPR], ephotozine [EPZ], photographyblog [PB]). As can be seen, the professional reviewers agree in many cases on the quality of different cameras, but sometimes their assessments diverge, reinforcing the earlier point that a camera decision is often a very personal choice.
|1.||Pentax 645Z||5/5||..||..||4.5/5||5/5||Apr 2014||8,499|
|2.||Sony RX10||5/5||+||80/100||4.5/5||4.5/5||Oct 2013||1,299|
|3.||Canon 1D X Mark II||..||..||89/100||4.5/5||4.5/5||Feb 2016||5,999|
|4.||Canon 5DS||..||+||83/100||4.5/5||4.5/5||Feb 2015||3,699|
|5.||Canon 5DS R||5/5||+||83/100||5/5||4.5/5||Feb 2015||3,699|
|6.||Canon G3 X||3.5/5||+||..||4.5/5||4/5||Jun 2015||999|
|7.||Canon 70D||5/5||+ +||83/100||4.5/5||5/5||Jul 2013||1,199|
|8.||Hasselblad X1D||..||o||81/100||..||4/5||Jun 2016||8,995|
|9.||Leica SL||4/5||..||84/100||4.5/5||4/5||Oct 2015||7,450|
|10.||Nikon D850||4.5/5||+ +||89/100||4.5/5||5/5||Jul 2017||3,299|
|11.||Nikon D5||..||..||89/100||4.5/5||5/5||Jan 2016||6,499|
|12.||Nikon D7200||4/5||+ +||84/100||4.5/5||4.5/5||Mar 2015||1,199|
|13.||Nikon D4S||5/5||..||..||4.5/5||4.5/5||Feb 2014||6,499|
|14.||Nikon D7100||5/5||+ +||85/100||4.5/5||4.5/5||Feb 2013||1,199|
|15.||Panasonic FZ1000||4/5||+ +||82/100||4.5/5||4.5/5||Jun 2014||899|
|16.||Pentax 645D||5/5||..||..||..||..||Mar 2010||9,995|
|17.||Sony RX10 II||5/5||+ +||82/100||4.5/5||4/5||Jun 2015||1,299|
|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 645Z vs Sony RX10
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 645Z||Sony RX10|
|Camera Type||Digital single lens reflex||Fixed lens compact camera|
|Camera Lens||Pentax 645 mount lenses||24-200mm f/2.8|
|Launch Date||April 2014||October 2013|
|Launch Price||USD 8,499||USD 1,299|
|Sensor Specs||Pentax 645Z||Sony RX10|
|Sensor Format||Medium Format Sensor||1" Sensor|
|Sensor Size||43.8 x 32.8 mm||13.2 x 8.8 mm|
|Sensor Area||1436.64 mm2||116.16 mm2|
|Sensor Diagonal||54.7 mm||15.9 mm|
|Sensor Resolution||51.1 Megapixels||20 Megapixels|
|Image Resolution||8256 x 6192 pixels||5472 x 3648 pixels|
|Pixel Pitch||5.30 μm||2.41 μm|
|Pixel Density||3.56 MP/cm2||17.18 MP/cm2|
|Moiré control||no AA filter||Anti-Alias filter|
|Movie Capability||1080/60i Video||1080/60p Video|
|ISO Setting||100 - 204,800 ISO||125 - 12,800 ISO|
|ISO Boost||no Enhancement||80 - 25,600 ISO|
|Image Processor||PRIME III||BIONZ X|
|DXO Sensor Quality (score)||101||69|
|DXO Color Depth (bits)||26.0||22.9|
|DXO Dynamic Range (EV)||14.7||12.6|
|DXO Low Light (ISO)||4505||474|
|Screen Specs||Pentax 645Z||Sony RX10|
|Viewfinder Type||Optical viewfinder||Electronic viewfinder|
|Viewfinder Field of View||98%||100%|
|Viewfinder Resolution||1440k dots|
|Top-Level Screen||Control Panel||Control Panel|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.2inch||3.0inch|
|LCD Resolution||1037k dots||1229k dots|
|LCD Attachment||Tilting screen||Tilting screen|
|Shooting Specs||Pentax 645Z||Sony RX10|
|Focus System||Phase-detect AF||Contrast-detect AF|
|Manual Focusing Aid||Focus Peaking||Focus Peaking|
|Max Shutter Speed (mechanical)||1/4000s||1/3200s|
|Continuous Shooting||3 shutter flaps/s||10 shutter flaps/s|
|Time-Lapse Photography||Intervalometer built-in||no Intervalometer|
|Fill Flash||no On-Board Flash||Build-in Flash|
|Storage Medium||SDXC cards||MS or SDXC cards|
|Second Storage Option||Dual card slots||Single card slot|
|UHS card support||UHS-I||UHS-I|
|Connectivity Specs||Pentax 645Z||Sony RX10|
|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||no Headphone port||Headphone port|
|Wifi Support||no Wifi||Wifi built-in|
|Near-Field Communication||no NFC||NFC built-in|
|Body Specs||Pentax 645Z||Sony RX10|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||650 shots per charge||420 shots per charge|
|In-Camera Charging||no USB charging||USB charging|
156 x 117 x 123 mm
(6.1 x 4.6 x 4.8 in)
129 x 88 x 102 mm
(5.1 x 3.5 x 4.0 in)
|Camera Weight||1550 g (54.7 oz)||813 g (28.7 oz)|
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