Pentax K-3 vs Canon EOS 70D vs Olympus OM-D E-M1 Comparison

October 9, 2013

Pentax K-3, Olympus OM-D E-M5 and Canon 70D side by side on a metal dark background

In this article we are going to have an interesting comparison. I will be comparing the newly announced Pentax K-3 (APS-C DSLR) versus Canon EOS 70D (APS-C DSLR) and Olympus OM-D E-M1 (Micro Four Thirds Compact System Camera).  The Pentax K-3 is probably one of the most interesting and innovative DSLR cameras this year. The K-3 doesn’t directly replace the K-5, and was designed to sit alongside it. Nevertheless, I know that some of you want to know what’s so special about the K-3, and whether or not it would be wiser to buy the Canon 70D or go with Olympus’ latest flagship model, the E-M1?

In this comparison article I’ll do my best to give you the information that you need to know in order to make that decision. I personally think that all three are highly capable enthusiast interchangeable lens cameras, but you need to better understand the difference before making your final decision.

In each section I will focus on different aspects of the camera, allowing you to get familiar with the differences in each section individually. Some people give more attention to the camera body features, others might find the camera’s performance more useful for his specific shooting style. No matter what your preferences are, just follow along and I’m pretty sure that by the end of the article, you’ll get a good idea which camera fits you best. So without further ado, let’s begin.


Before we jump on talking about the camera’s key features, let’s first check to which price segment each camera belongs — and whether or not there is a camera that falls out of your budget.

Prices via as for October 9th, 2013 (visit for updated prices).

  • Pentax K-3
    Body only: $1299. 00
    With 18-135mm WR lens:  $1649. 00
  • Canon EOS 70D
    Body only:  $1199. 00
    With  18-135mm EF-S IS STM lens: $1549. 00
    With 18-55mm EF-S STM lens:  $1349. 00
  • Olympus OM-D E-M1
    Body only: $1399. 00

Looking at the body-only offering, we can see that the Canon EOS 70D is the cheapest one at approx. $1200, followed by Pentax K-3 which costs $100 more, followed by Olympus OM-D E-M1 that costs $200 more than the 70D.

Some people come with a thought that a Compact System Camera should cost less than a DSLR — in some cases it’s true, but it depends on the specific model, and we are looking at a flagship compact system camera,  Olympus best Micro Four Thirds cameras, and therefore it’s priced accordingly.
Having said that, for some of you, $200 might not be a barrier at all, especially if you are already considering paying more than a grand on a camera. Of course it’s important to understand what do you get in return of your investment when you pay for the more expensive model. In some cases, you might find out that those features that you are paying that extra money for are not useful for your shooting habits at all — so you better save that money and buy an additional lens or accessory for your camera.

Camera Design

Each camera has its unique design, build-quality, different button layout and features.  The Olympus OM-D E-M1 is the smallest and lightest camera in the group, although compare to other CSC, is not that small.

The E-M1 follows the same design concept as Olympus retro OM cameras from the 70s.  I personally like that retro design look and feel, but some of you might favor the more traditional look and feel of the 70D and K-3.

Pentax K-3 vs Canon EOS 70D vs Olympus OM-D E-M1 cameras side by side

Pentax K-3 vs Canon EOS 70D vs Olympus OM-D E-M1 size comparison (via

Now let’s take a look at the cameras from the top.

Pentax K-3, Olympus OM-D E-M5 and Canon EOS 70D comparison

Pentax K-3, Olympus OM-D E-M1 and Canon EOS 70D Top View size comparison (via

You can clearly see that the OM-D E-M1 is much slimmer due to the lack of a reflex mirror (aka ‘mirrorless’), which allows camera manufacturers to create smaller cameras, as well as smaller lenses compare to the SLR APS-C cameras counterpart.

The E-M1 also lacks the top LCD display which some photographers find useful. It allows a quick glance of some of the important camera settings as well as helps reduce the power consumption and saves battery power because you don’t need to check the menu to view the current settings. Some of the camera settings can be viewed via the viewfinder, but let’s not forget that both the K-3 and 70D have an optical viewfinder, whether the E-M1 has an electronic viewfinder. This, alongside a larger battery capacity, gives the K-3 (560 shots CIPA) and EOS 7D (920 shots) an advantage over the E-M1 (350 shots) when it comes to shooting capacity on a single battery charge.

The battery life is in fact one compromise that photographers make when they pick up a relatively small compact system camera.

Weather Sealing and Body Construction

The weather-sealing protection degree is quite confusing when it comes to cameras, which unlike watches or smartphones—it doesn’t have a liquid ingress protection rating (IP) or any other type rating to make it easy to compare one camera versus the other. Having said that, let’s focus on what we do know instead of what we don’t.

Canon EOS 70D Weather sealing and Body Construction

Weather sealing, Canon 70D

Weather sealing illustration, Canon EOS 70D (image credit: Canon)

  • Stainless Steel + polycarbonate with glass fiber
  • 100,000 shutter cycles
  • Its dust and moisture resistance performance is the same as that on the EOS 60D.” (via
    Water / Dust Resistance: Yes (equal to EOS-1N)” – via

The EOS 70D has the same weather-resistant level as the EOS-1N, and the EOS 1N has the same weather sealing protection as the Canon EOS 3. This means that the buttons and dials has rubber gaskets that prevent water droplets to get into the camera.

Although I’ve read many comments about shooting with the 70D in the rain without any issues, some people did report issues when shooting it in the rain. So as far as I understood it, I wouldn’t shoot with the 70D in the rain and risk it. However, if you accidentally exposed your camera in the rain or had water splashes on it in some degree, it should survive it.

Pentax K-3 Weather sealing and Body Construction

Pentax K-3 magnesium alloy body and metal chasisWith the Pentax K-3 it seems like a different story, as Pentax marketed some of its DSLR cameras, as well as the K-3 as a very durable and weather-sealed camera for the outdoor photographer.

  • Magnesium alloy body with stainless steel chassis
  • 200,00 shutter cycles
  • Weather resistant body with 92 protection seals“, “..fully weather and cold proof design to resist water, fog, snow, sand, and dust..” (via
    Can operate down to 14 degrees Fahrenheit  (-10 degrees Celsius)

The Pentax K-3 is built with excellent durability and high-degree of weather sealing capability. You can shoot with this camera in the rain or in the snow without worrying about any damage happening to your camera — but keep in mind that the K-3 is not a waterproof camera.
Olympus OM-D E-M1 Weather sealing and Body Construction

The Olympus OM-D E-M1, like the K-3 is also marketed as a highly durable camera.

  • Metal outer frame, magnesium alloy inner frame
  • Olympus doesn’t rate the shutter life, but I assume that it’s between 100,000 – 150,000 clicks
  • Rain or snow, mud or dust …“, “freezeproof, Dustproof, Splash proof” (via
    Can operate down to 14 degrees Fahrenheit   (-10 degrees Celsius)

So Olympus doesn’t leave us with open questions. We know that the E-M1 can withstand rain and water splashes, so you should be fine shooting with it in the rain, without worrying about any damage to your camera.

Both the K-3 and E-M1 wins in the durability department. If you are planning a trip to Alaska or planning to shooting in a very humid environment — I would probably recommend getting either the K-3 or the E-M1 for the task. The 70D might hold on the same as well, but there is little information about its durability, and there are already people who have bad experience with it when shooting in the rain. Both the E-M1 and K-3 are more rugged and therefore can better withstand bumps and drops if those accidentally occur when shooting outdoors.

Button Layout

Canon EOS 70D — In terms of button layout, all three have lots of buttons and dials to allow fast access to frequently used camera settings. The EOS 70D is the largest camera in the group, but takes advantage of that size. For example, at the top-right side you can find 5 rounded buttons for the ISO speed, Metering mode, AF area area, Drive mode and AF mode. At the back you can find the AE lock/FE lock button, AF point selection button, etc. The main dial is also placed at the top instead of the back to allow more room for the thumb, as well as a place for the three AF control buttons.

Pentax K-3 — is smaller than the Canon 70D. There is less room for the thumb at the back and most of the buttons are placed at the back instead of the top. The K-3 has a dedicated switch for changing from stills to movie recording mode. The K-3 like the other two cameras has a mode dial with lock-release button.
Unlike the Canon EOS 70D which has one main mode dial, the K-3 features two dials, one at the rear right side and one and one at the front.  For example, you can use the rear dial to change the aperture and the front dial to change the shutter speed. This allows faster operation because you don’t to manually switch to another camera setting of the dial, now that you have two of them.

Olympus OM-D E-M1 — is the smallest camera of the three and everything is more crowded. It might be less comfortable to hold for people with large hands. At the top you can find a front dial with the shutter button inside (Olympus is saving space there), Fn2 button, rear dial (so we have two separate dials like the K-3), HDR/self-timer/drive button, etc.  At the back you can find the second Fn1 button and other buttons to control the exposure, focus and navigation buttons.
I think that Olympus did the best it arranging those buttons in the optimal layout. After all, this is a semi-pro level camera and those buttons are crucial for the fast camera operation for the audience that this camera is aimed for. Of course there isn’t any place for a top LCD display, which I personally learned to leave without it, but using the rear LCD does have an impact on the battery life.

The E-M1 also has the smallest grip of the three. Mirrorless cameras were designed from the get go to be smaller and lighter. However, the E-M1 is certainly not a pocketable camera and you’ll need a camera bag to carry it around, especially when you plan to carry more than one lens or extra accessories. So you might as well purchase the Olympus HLD-7 camera grip for the E-M1, which can give you that extra grip if you need it.

LCD and Eye-level Viewfinder

The viewfinder and the LCD play a significant role when buying a camera. The better the size and the resolution, the better. Let’s take a look at the specs first.

  • Olympus OM-D E-M1
    LCD — 3″ / 1037K-dots / touchscreen / tilting
    Viewfinder  — EVF / 100% coverage / 1.48x magnification (0.74x equivalent) / 2.36M-dots
  • Pentax K-3
    LCD — 3.2″ / 1037K-dots / not touchscreen / fixed
    Viewfinder  — OVF Pentaprism / 100% coverage / 0.95x (0.63x equivalent) + improved design and new coating to improve the viewfinder brightness
  • Canon EOS 70D
    LCD — 3″ / 1040K-dots / touchscreen / fully articulated
    Viewfinder  — OVF Pentaprism / 98% coverage / 0.95x (0.63x equivalent)

Oly E-M1 has an electronic viewfinder, rather than an optical viewfinder. Some people prefer an optical viewfinder, others don’t mind using an EVF as long as its a good one — and indeed the E-M1 EVf has 100% coverage and 2.36M dot resolution, 29 ms image display lag and an eye sensor to automatically switch between the EVF and the monitor to save battery. So although you don’t get an optical viewfinder with real-time TTL view as the K-3 and the 70D, you can comfort yourself that at least you get a very high quality EVF.

The Canon EOS 7D has the most versatile rear display. It allows touch operation, as well as fully articulated which is a favorite feature among Videographers.   So in this section, I would give my top score to the EOS 70D, followed by OM-D E-M1 and K-3 in the third position.

In-body Image Stabilization (IBIS)

Both the Olympus OM-D E-M1 and the Pentax K-3 employ a built-in sensor-shift image stabilization mechanism to reduce the occurrence of blurring in images when shooting handheld with slow shutter speed, under the one recommended for a particular focal length (1/focal length shutter speed is the shutter speed rule of thumb).

The Canon EOS 70D lacks this feature, like all Canon DSLR cameras. This means that if you want / need an image stabilization, you’ll need to purchase a lens with ‘IS’. The downside is obviously the high price that you need to pay compared to a non-stabilized lens. For some lenses like telephoto-zoom lenses this is a must, especially if you shoot most of your photos without a tripod.

For the E-M1 and K-3 it means that whatever lens you attack to the camera, it will immediately become stabilized. If you mount a Panasonic stabilized Micro Four Thirds lens on the E-M1, you have the option to give priority to the lens and use the lens’ IS instead of the built-in one.

Let’s take a look at the E-M1 and K-3 image stabilization specs:

  • E-M1 – 5-axis image stabilization with different modes:
    Stills: Off, On (auto), S-IS2 (Vertical IS, use when panning the camera), S-IS3 (Horizontal IS), S-IS Auto (automatically detected the panning direction)
    Movies: Off, On
  • K-3 – Pentax Shake Reduction (SR) system 3-axis IBIS (vertical shift, horizontal shift, rotational motion)
    3,5EV compensation (TBD)

The E-M5, E-P5 and E-M1 have that 5-axis IBIS. This is by far the most advanced image stabilization available in any camera on the market right now. It compensated for tilting, turning, vertical shifting, horizontal shifting and camera roll along the optical axis.

This is certainly a big advantage for both the E-M1 and K-3, although some photographer might prefer the lens-shift optical image stabilization — but again, there isn’t any lens-shift optical image stabilization that compensated for 5-axis as the E-M1. One of the advantages of having the IS in the lens is that you get to see the stabilization effect through the viewfinder (in SLR cameras).

Another unique feature of the K-3 is that it utilizes the microscopic movements for the image stabilization mechanism in order to mimic the effect of an optical low-pass filter. The K-3 lacks the OLPF, and we’ll talk about that in the next section.

With OLPF or Without – That is The Question (Hey, Why not both?)

Both the Olympus OM-D E-M1 and Pentax K-3 lack the Low-Pass filter, whether the Canon EOS 70D has the low-pass filter built-in with fluorine coating. There are many companies who follow this trend and release interchangeable lens cameras without the anti-aliasing filter. The goal is to squeeze as much information from the scene as possible, but knowing the drawback in advance that can cause dramatic Moiré patterns, depends on the scene.

The anti-aliasing filter (also referred to as “Blue filter”) was designed to combat this phenomenon.  There are many reviewers who find the difference (more details) to be almost negligible, and although the difference is there, it’s mainly visible only when you look at the image at 100% scale.  Dpreview compared the Nikon D800 vs the D800e (the one without the OLPF), and found a very slight difference. Ken Rockwell did the same test and came to the same conclusion.

With the E-M1 you need to accept that in some scenes you’ll get more severe moire patterns. Pentax however solves this problem by offering the photographer two options. The Pentax K-3 sensor lacks the anti-aliasing filter, but Pentax utilizes the shake reduction system in a way that it vibrates and mimics the effect of a blur filter by using microscopic movements at the pixel level. Pentax refers to this as “AA filter simulator” (see the video below to understand how it works).

So you, the photographer, have control over this effect and you can select whether you want to turn the AA filter simulator on or off. Very innovative idea, isn’t it? — You don’t need to break your head whether to buy a camera with or without an AA filter. So in this regard, the Pentax K-3 takes the first place and you’ll decide whether or not this feature is important to you or not.

Other Features

In this section I will use a side by side comparison table to compare some other key features of those three cameras.

Sensor16MP (effective)
Micro Four Thirds (17.3x13mm)
Dual Pixel CMOS AF
24MP (effective)
APS-C (23.5x15.6mm)
20MP (effective)
APS-C (22.5x15mm)
Image ProcessorTruePic VIIPrime IIIDigic 5+
(25600 with boost)
AF Points81 (see notes below)2719
70D feature on-sensor phase-detection which allows the camera to use phase-detection algorithms when shooting videos.

This technology promotes faster and more accurate AF during video capture or when shooting still in Live View mode.

All the effective pixels on the sensor consist of two individual photodiodes. Those two are read separately and provide the data needed for the phase-detection algorithm, and all that without compromising on image quality (more information can be found here).

The E-M1 has 81 AF points, highest of the three, allowing more responsive and accurate subject tracking.

The E-M1 has what is called "Dual Fast AF". This means that when you mount a Micro Four Thirds lens, the camera will use 81-point multiple contrast-detection AF and the phase-detection AF points. When you mount a Four Thirds lens using the adapter, the camera will use 37-point multiple phase-difference detection AF -- each optimize to maximize the capabilities for each lens system.
Shutter Speed60-1/8000 sec30-1/8000 sec60-1/8000 sec
Built-in FlashNo (compact external flash included in the package - depends on location. See this forum post on dpreview)YesYes
Wireless Flash CommanderYesYesYes
Flash X Sync1/320 sec1/180 sec1/250 sec
Exposure Compensation±5 (at 1/3 EV, 1/2 EV, 1 EV steps)±5 (at 1/3 EV, 1/2 EV steps)±5 (at 1/3 EV, 1/2 EV steps)
WB BracketingYesNoYes
Video Recording1080p30
Mic InputYesYesYes
Headphone JackNoYesNo
Built-in Wi-FiYesNo (via Flucard)Yes
Battery Life (CIPA)350560920
Official Battery GripYes, Olympus HLD-7 Camera Grip YesYes, Canon battery grip for EOS 70D
Remote ControlYes (optional)Yes (optional)Yes (optional)
Built-in Timelapse RecordingYesYesNo (only using USB cable and PC)
Continuous Shooting6.5 fps (50 JPG, 50 RAW)8.3 fps (60 JPG, 23 RAW)
10 fps in "H Mode" (focus and exposure are fixed in first shot)
7 fps (65 shots, 16 RAW - based on 8GB UHS-I card)
Dual Card SlotNoYesNo
Light Metering Sensor324-area multi pattern metering

EV -2 - 20 metering range
86K pixel RGB sensor

EV -3 to 20 metering range
FCL 63-Zone Dual Layer Metering sensor

EV 1-20 metering range

Olympus OM-D E-M1 cons and pros (according to the specs comparison  table above):

  • 81 point AF system (contrast-detect)
  • Fastest flash x sync speed (1/320 sec)
  • Second in the highest native maximum ISO
  • 60 sec minimum shutter speed (same as 70D)
  • WB bracketing (same as the 70D)
  • Built-in Wi-Fi (same as the 70D)
  • Built-in timelaspe recording (same as the K-3)
  • 324-area light metering sensor, second in sensor’s sensitivity
  • Built-in stereo mic (same as 70D)
  • No built-in Flash
  • No headphone jacks
  • Slowest burst in the group
  • No dual card slot
  • Least amount of video frame rates

Pentax K-3 cons and pros:

  • Highest sensor resolution in the group (can be a disadvantage depends how other aspects and on its high ISO performance, but in low ISO will result in higher details)
  • Highest ISO range in the group
  • Has headphone jack for audio monitoring
  • Fastest continuous shooting in the group (impressive considering its sensor resolution!)
  • Dual SD card slot
  • Most advanced light metering system (based on number of sensors) and the most sensitive one (EV -3)
  • Second in number of AF points
  • Has pop up flash (same as the 70D)
  • Second highest battery life in the group
  • Built-in time lapse recording (same as the E-M1)
  • No headphone jack (same as E-M1)
  • Last in the slowest shutter speed
  • Slowest flash x sync speed
  • No WB bracketing
  • No built-in Wi-Fi (available via Flucard)

Canon EOS 70D cons and pros:

  • Best Battery life in the group (by far)
  • Being able to choose between IPB or All-I video compression
  • Second in the number of frame rates available for video recording
  • 60 sec shutter speed (same as E-M1)
  • Second fastest flash sync speed
  • WB bracketing (as E-M1)
  • Second in frame rate options for video recording
  • Built-in stereo mic (same as E-M1)
  • Second in fastest continuous shooting speed
  • No dual card slot (same as E-M1)
  • No headphone jack
  • Lowest maximum native ISO
  • Lowest AF points (for stills)
  • No built-in timelapse recording
  • The least sensitive light metering sensor


When you compare the Pentax K-3 versus the Olympus OM-D E-M1 and Canon EOS 70D you can see why so many people were so excited about this new camera. It’s $100 less expensive than the E-M1, but offers a wide range of useful features, including high-res sensor, very fast burst speed at full-res, dual SD card slot, in-body stabilization, advanced AF system and light metering sensor, etc.
If I had to buy a new DSLR and I would certainly put the K-3 in the top of my list. The K-3 has its advantage over the E-M1, and quite a few of them, including higher max. ISO sensitivity, much higher resolution, 2 card slots, longer battery life, larger sensor, 720p60 video recording (60 fps / progressive frames), selectable anti-aliasing filter,  OVF, larger display and above all that it’s $100 cheaper.

In my opinion, those features that are unique to the K-3 easily worth $100, don’t you think?
The OM-D E-M1 on the other hand has its unique features as well, including: 5-axis IBIS, built-in Wi-Fi, touch-sensitive tilting display, much more AF points, it’s smaller and slimmer and weight significantly less and fast flash x sync speed.

So where the Canon EOS 70D fits in all this. First of all, it’s the cheapest in the group. It features the largest body and excellent ergonomics. The battery life is the best in the group. EOS 70D is a movie-oriented camera and the best HDSLR in the group, offering the ability to choose the video compression, phase-detection for movie recording, built-in stereo mic, mic jack to connect and external mic and a fully articulated LCD for easier low and high-angle composition.

If you find yourself shooting lots of movies, the Canon EOS 70D might be the best camera for you.  I personally find the Pentax K-3 more appealing as a stills camera and I really like its innovative features and smaller size factor.
I know that the decision isn’t easy, but there are certainly some differences that are unique to each camera and might convince you to get one camera over the other due to these unique features. Pentax released an amazing APS-C DSLR camera, but let’s remember that Pentax still doesn’t have a full frame DSLR. There are rumors running around rumors websites about a Pentax full frame DSLR, but those are only rumors.

If you plan to buy a full frame DSLR somewhere in the future, buying the Canon EOS 7D is probably the best way to go, especially if you already have or plan to buy a few full frame lenses.

So take all the differences and the upgrade option into account when making a decision.

Click here to buy the Pentax K-3 from B&H Photo store

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