Olympus E-M5 vs Pentax K-3
The Olympus OM-D E-M5 and the Pentax K-3 are two enthusiast cameras that were officially introduced, respectively, in February 2012 and October 2013. The E-M5 is a mirrorless interchangeable lens camera, while the K-3 is a DSLR. The cameras are based on a Four Thirds (E-M5) and an APS-C (K-3) sensor. The Olympus has a resolution of 15.9 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.
|Olympus E-M5||Pentax K-3|
|Mirrorless system camera||Digital single lens reflex|
|Micro Four Thirds lenses||Pentax K mount lenses|
|15.9 MP, Four Thirds Sensor||24.1 MP, APS-C Sensor|
|1080/60i Video||1080/60i Video|
|ISO 200-25,600||ISO 100-51,200|
|Electronic viewfinder (1440k dots)||Optical viewfinder|
|3.0 LCD, 610k dots||3.2 LCD, 1037k dots|
|Tilting touchscreen||Fixed screen (not touch-sensitive)|
|9 shutter flaps per second||8.3 shutter flaps per second|
|In-body stabilization||In-body stabilization|
|Weathersealed body||Weathersealed body|
|360 shots per battery charge||560 shots per battery charge|
|122 x 89 x 43 mm, 425 g||131 x 100 x 77 mm, 800 g|
Going beyond this snapshot of core features and characteristics, what are the differences between the Olympus OM-D E-M5 and the Pentax K-3? 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 Olympus E-M5 and the Pentax K-3. 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.
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 is notably larger (21 percent) than the Olympus E-M5. Moreover, the K-3 is substantially heavier (88 percent) than the E-M5. 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.
The table below summarizes the key physical specs of the two cameras alongside a broader set of comparators. If you want to switch the focus of the display and review another camera pair, just select a new right or left comparator from among the camera models in the table. Alternatively, you can also move across to the CAM-parator tool and choose from the broad selection of possible camera comparisons there.
|Olympus E-M5||4.8 in||3.5 in||1.7 in||15.0 oz||360||Y||Feb 2012||1,299|
|Pentax K-3||5.2 in||3.9 in||3.0 in||28.2 oz||560||Y||Oct 2013||1,299|
|Olympus PEN-F||4.9 in||2.8 in||1.5 in||15.1 oz||330||n||Jan 2016||1,199|
|Olympus E-M5 II||4.9 in||3.3 in||1.8 in||16.5 oz||310||Y||Feb 2015||1,099|
|Olympus E-PL7||4.5 in||2.6 in||1.5 in||12.6 oz||350||n||Aug 2014||599|
|Olympus E-M1||5.1 in||3.7 in||2.5 in||17.5 oz||350||Y||Sep 2013||1,399|
|Olympus E-P5||4.8 in||2.7 in||1.5 in||14.8 oz||330||n||May 2013||999|
|Olympus E-PL5||4.4 in||2.5 in||1.5 in||11.5 oz||360||n||Sep 2012||599|
|Olympus E-PM2||4.3 in||2.5 in||1.3 in||9.5 oz||360||n||Sep 2012||499|
|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|
|Panasonic GH3||5.2 in||3.7 in||3.2 in||19.4 oz||540||Y||Sep 2012||1,299|
|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 II||5.2 in||3.9 in||3.0 in||28.2 oz||720||Y||Apr 2015||1,099|
|Pentax K-5||5.2 in||3.8 in||2.9 in||26.8 oz||740||Y||Sep 2010||1,099|
|Sony A77||5.6 in||4.1 in||3.2 in||25.8 oz||470||Y||Aug 2011||1,399|
Notes: Measurements and pricing do not include easily detachable parts, such as add-on or interchangeable lenses or optional viewfinders.
(1) Number of images that can be taken on a full battery charge according to the CIPA-standard; (2) Official announcement.
Any camera decision will naturally be influenced heavily by the price. 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 two cameras under review were launched at the same price and fall into the same market segment. Normally, street prices remain initially close to the MSRP, but after a couple of months, the first discounts appear. Later in the product cycle and, in particular, when the replacement model is about to appear, further discounting and stock clearance sales often push the camera price considerably down.
The size of the sensor inside a digital camera is one of the key determinants of image quality. All other things equal, a large sensor will have larger individual pixel-units that offer better low-light sensitivity, wider dynamic range, and richer color-depth than smaller pixels in a sensor of the same technological generation. 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 Olympus E-M5 features a Four Thirds sensor and the Pentax K-3 an APS-C sensor. The sensor area in the K-3 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 E-M5 has a native 4:3 aspect ratio, while the one in the K-3 offers a 3:2 aspect.
With 24.1MP, the K-3 offers a higher resolution than the E-M5 (15.9MP), but the K-3 nevertheless has larger individual pixels (pixel pitch of 3.90μm versus 3.76μm for the E-M5) due to its larger sensor. Moreover, the K-3 is a somewhat more recent model (by 1 year and 7 months) than the E-M5, 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 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.
The resolution advantage of the Pentax K-3 implies greater flexibility for cropping images or the possibility to print larger pictures. The maximum print size of the K-3 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 Olympus E-M5 are 23 x 17.3 inches or 58.5 x 43.9 cm for good quality, 18.4 x 13.8 inches or 46.8 x 35.1 cm for very good quality, and 15.4 x 11.5 inches or 39 x 29.3 cm for excellent quality prints.
The Olympus OM-D E-M5 has a native sensitivity range from ISO 200 to ISO 25600. The corresponding ISO settings for the Pentax K-3 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. Of the two cameras under consideration, the K-3 has a markedly higher DXO score than the E-M5 (overall score 9 points higher), which will translate into better image quality. The advantage is based on 0.9 bits higher color depth, 1.1 EV in additional dynamic range, and 0.6 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.
|Olympus E-M5||Four Thirds||15.9||4608||3456||1080/60i||22.8||12.3||826||71|
|Olympus PEN-F||Four Thirds||20.2||5184||3888||1080/60p||23.1||12.4||894||74|
|Olympus E-M5 II||Four Thirds||15.9||4608||3456||1080/60p||23.0||12.5||842||73|
|Olympus E-PL7||Four Thirds||15.9||4608||3456||1080/30p||22.7||12.4||873||72|
|Olympus E-M1||Four Thirds||15.9||4608||3456||1080/30p||23.0||12.7||757||73|
|Olympus E-P5||Four Thirds||15.9||4608||3456||1080/30p||22.8||12.4||895||72|
|Olympus E-PL5||Four Thirds||15.9||4608||3456||1080/30p||22.8||12.3||889||72|
|Olympus E-PM2||Four Thirds||15.9||4608||3456||1080/30p||22.7||12.2||932||72|
|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|
|Panasonic GH3||Four Thirds||15.9||4608||3456||1080/60p||22.7||12.4||812||71|
|Pentax K-3 II||APS-C||24.1||6016||4000||1080/60i||23.6||13.6||1106||80|
Many modern cameras are not only capable of taking still images, but also of capturing video footage. The two cameras under consideration both have sensors whose read-out speed is fast enough to capture moving pictures, and both provide the same movie specifications (1080/60i).
Apart from body and sensor, cameras can and do differ across a variety of features. For example, the E-M5 has an electronic viewfinder (1440k dots), while the K-3 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 K-3 has a higher magnification than the one of the E-M5 (0.63x vs 0.58x), 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 Olympus E-M5, the Pentax K-3, and comparable cameras.
|Olympus E-M5 II||2360||n||3.0||1037||swivel||Y||1/8000s||10.0||n||Y|
|Pentax K-3 II||optical||Y||3.2||1037||fixed||n||1/8000s||8.3||n||Y|
One differentiating feature between the two cameras concerns the touch sensitivity of the rear screen. The E-M5 has a touchscreen, while the K-3 has a conventional panel. Touch control can be particularly helpful, for example, for setting the focus point.
The Pentax K-3 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.
Concerning the storage of imaging data, both the E-M5 and the K-3 write their files to SDXC cards. The K-3 features dual card slots, which can be very useful in case a memory card fails. In contrast, the E-M5 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 Olympus OM-D E-M5 and Pentax K-3 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.
| WiFi |
|Olympus E-M5 II||Y||stereo||mono||Y||-||micro||2.0||Y||-||-|
|Pentax K-3 II||Y||mono||mono||Y||Y||mini||3.0||-||-||-|
It is notable that the K-3 has a headphone jack, which makes it possible to attach external headphones and monitor the quality of sound during the recording process. The E-M5 lacks such a headphone port.
Studio photographers will appreciate that the Pentax K-3 (unlike the E-M5) features a PC Sync socket, so that professional strobe lights can be controlled by the camera.
Both the E-M5 and the K-3 have been discontinued, but can regularly be found used on eBay. The E-M5 was replaced by the Olympus E-M5 II, while the K-3 was followed by the Pentax K-3 II. Further information on the two cameras (e.g. user guides, manuals), as well as related accessories, can be found on the official Olympus and Pentax websites.
So how do things add up? Is the Olympus E-M5 better than the Pentax K-3 or vice versa? Below is a summary of the relative strengths of each of the two contestants.
Arguments in favor of the Olympus OM-D E-M5:
- Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.
- More framing info: Has an electronic viewfinder that displays shooting data.
- 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.
- More compact: Is smaller (122x89mm vs 131x100mm) and thus needs less room in the bag.
- Less heavy: Is lighter (by 375g or 47 percent) and hence easier to carry around.
- More legacy lens friendly: Can take a broad range of non-native lenses via adapters.
- More heavily discounted: Has been on the market for longer (launched in February 2012).
Reasons to prefer the Pentax K-3:
- More detail: Has more megapixels (24.1 vs 15.9MP), which boosts linear resolution by 25%.
- Maximized detail: Lacks an anti-alias filter to exploit the sensor's full resolution potential.
- Better image quality: Scores markedly higher (9 points) in the DXO overall evaluation.
- More dynamic range: Captures a broader range of light and dark details (1.1 EV of extra DR).
- Better low-light sensitivity: Can shoot in dim conditions (0.6 stops ISO advantage).
- 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.
- Larger viewfinder image: Features a viewfinder with a higher magnification (0.63x vs 0.58x).
- 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.
- More detailed LCD: Has a higher resolution rear screen (1037k vs 610k dots).
- Faster shutter: Has higher mechanical shutter speed (1/8000s vs 1/4000s) to freeze action.
- Easier time-lapse photography: Has an intervalometer built-in for low frequency shooting.
- Longer lasting: Gets more shots (560 versus 360) out of a single battery charge.
- Easier fill-in: Has a small integrated flash to brighten shadows of backlit subjects.
- 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: Was introduced somewhat (1 year and 7 months) more recently.
If the count of relative strengths (bullet points above) is taken as a measure, the K-3 is the clear winner of the contest (20 : 8 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 Olympus E-M5 and the Pentax K-3 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 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 E-M5 or the K-3. User reviews, such as those found at amazon, can sometimes inform about these issues, but such feedback is often incomplete, inconsistent, and biased.
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.
|Olympus E-M5||+ +||80/100||4.5/5||5/5||5/5||Feb 2012||1,299|
|Pentax K-3||..||83/100||5/5||4.5/5||5/5||Oct 2013||1,299|
|Olympus PEN-F||..||82/100||4.5/5||4.5/5||5/5||Jan 2016||1,199|
|Olympus E-M5 II||+ +||81/100||5/5||4.5/5||5/5||Feb 2015||1,099|
|Olympus E-PL7||+||..||5/5||4.5/5||4/5||Aug 2014||599|
|Olympus E-M1||+ +||84/100||4.5/5||4.5/5||4.5/5||Sep 2013||1,399|
|Olympus E-P5||+ +||78/100||4.5/5||4.5/5||5/5||May 2013||999|
|Olympus E-PL5||+ +||..||4.5/5||4.5/5||4.5/5||Sep 2012||599|
|Olympus E-PM2||..||77/100||5/5||4.5/5||4.5/5||Sep 2012||499|
|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|
|Panasonic GH3||+ +||79/100||4.5/5||5/5||4.5/5||Sep 2012||1,299|
|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 II||..||..||5/5||4.5/5||5/5||Apr 2015||1,099|
|Pentax K-5||..||83/100||5/5||4.5/5||4.5/5||Sep 2010||1,099|
|Sony A77||91/100||81/100||..||4.5/5||5/5||Aug 2011||1,399|
|Notes: (+ +) highly recommended; (+) recommended; (o) reviewed; (..) not available.|
The review scores listed above should be treated with care, 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. Also, kindly note that some of the listed sites have over time developped their review approaches and their reporting style.
Other camera comparisons
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Specifications: Olympus E-M5 vs Pentax K-3
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||Olympus E-M5||Pentax K-3|
|Camera Type||Mirrorless system camera||Digital single lens reflex|
|Camera Lens||Micro Four Thirds lenses||Pentax K mount lenses|
|Launch Date||February 2012||October 2013|
|Launch Price||USD 1,299||USD 1,299|
|Sensor Specs||Olympus E-M5||Pentax K-3|
|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||15.9 Megapixels||24.1 Megapixels|
|Image Resolution||4608 x 3456 pixels||6016 x 4000 pixels|
|Pixel Pitch||3.76 μm||3.90 μm|
|Pixel Density||7.08 MP/cm2||6.56 MP/cm2|
|Moiré control||Anti-Alias filter||no AA filter|
|Movie Capability||1080/60i Video||1080/60i Video|
|ISO Setting||200 - 25,600 ISO||100 - 51,200 ISO|
|Image Processor||TruePic VI||PRIME III|
|DXO Sensor Quality (score)||71||80|
|DXO Color Depth (bits)||22.8||23.7|
|DXO Dynamic Range (EV)||12.3||13.4|
|DXO Low Light (ISO)||826||1216|
|Screen Specs||Olympus E-M5||Pentax K-3|
|Viewfinder Type||Electronic viewfinder||Optical viewfinder|
|Viewfinder Field of View||100%||100%|
|Viewfinder Resolution||1440k dots|
|Top-Level Screen||no Top Display||Control Panel|
|LCD Framing||Live View||Live View|
|Rear LCD Size||3.0inch||3.2inch|
|LCD Resolution||610k dots||1037k dots|
|LCD Attachment||Tilting screen||Fixed screen|
|Touch Input||Touchscreen||no Touchscreen|
|Shooting Specs||Olympus E-M5||Pentax K-3|
|Focus System||Contrast-detect AF||Phase-detect AF|
|Manual Focusing Aid||no Peaking Feature||Focus Peaking|
|Max Shutter Speed (mechanical)||1/4000s||1/8000s|
|Continuous Shooting||9 shutter flaps/s||8.3 shutter flaps/s|
|Shutter Life Expectancy||100 000 actuations||200 000 actuations|
|Time-Lapse Photography||no Intervalometer||Intervalometer built-in|
|Image Stabilization||In-body stabilization||In-body stabilization|
|Fill Flash||no On-Board Flash||Build-in 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||Olympus E-M5||Pentax K-3|
|Studio Flash||no PC Sync||PC Sync socket|
|USB Connector||USB 2.0||USB 3.0|
|HDMI Port||mini HDMI||mini HDMI|
|Microphone Port||no MIC socket||External MIC port|
|Headphone Socket||no Headphone port||Headphone port|
|Wifi Support||no Wifi||no Wifi|
|Body Specs||Olympus E-M5||Pentax K-3|
|Environmental Sealing||Weathersealed body||Weathersealed body|
|Battery Life (CIPA)||360 shots per charge||560 shots per charge|
122 x 89 x 43 mm
(4.8 x 3.5 x 1.7 in)
131 x 100 x 77 mm
(5.2 x 3.9 x 3.0 in)
|Camera Weight||425 g (15.0 oz)||800 g (28.2 oz)|
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