Pentax K-3 Mark III

a photographer’s review


My name is Mike Muizebelt and I’m a professional wildlife and nature photographer from the Netherlands. I’ve been using Pentax camera’s for over 30 years now and I’m a European Pentax brand ambassador. My current workhorses are the medium format Pentax 645Z and the full frame Pentax K-1’s.  On the 5th of February 2021, I received one of the first Pentax K-3 mark III’s to test it out in the field. In this review I’ll take you through my real-world experiences with this new APS-C flagship camera from Pentax.
As I had an early firmware on the camera and the RAW files were not supported by the software on my computer, I won’t discuss the technical qualities of the files. All images in this review were made with the Pentax K-3 mark III.

There is YouTube version of my finding as well. Click below to go to the video or browse to the bottom of this page.

Pentax K-3 Mark III low angle
Pentax K-3 mark III - DFA* 70-200 @F4 - 1/400s - ISO 800

Pentax K3 mark II – Ergonomics and Operation

The first thing you notice when you pick up the camera is it’s built quality. It has a very sturdy feel to it and I’ve got no doubt that it will survive the harsh conditions that I’m normally photographing in. Its fully weather sealed to withstand situations with ocean-spray, desert sand and extreme heat or cold.

The capacitive touchscreen is large and features 3 basis settings that can be switched to and from by pressing the info button:
– A status screen that displays your current settings like ISO, Aperture, horizon, AF mode and settings
– A quick adjustment screen with direct access to camera settings as HDR-Capture, Camera filters, Wireless LAN, file format, etc.
– Screen off
The layout of the menu has changed from a horizontal layout to a vertical layout, similar to that of the Ricoh GR3. For users familiar with Pentax’s settings and menu structure it will only take a few minutes to get used to. My Pentax K-3 mark III came without a manual but I had no problems at all to find the various settings.
Although the camera features a capacitive touchscreen, I found that most of the time I still use the 4-way buttons and function dials to navigate the menu and make adjustments. Old habits die hard I presume…

Pentax K3 mark III ducks
Pentax K-3 mark III - DFA 150-450 @5.6 - 1/1600s - ISO 1250

Pentax K-3 mark III – Technical Specifications

The K-3 mark III has received substantial improvements over its predecessor, the K-3 mark II.
I’ve discontinued my own Pentax K-3 already a few years ago as the K-1 and 645Z camera’s have much better performance and image resolution. The design of the K-3 was born in de mid 2010’s and although the K-3 mark III shares its name, it was a complete overhaul from the former design.
The camera is compatible with all previous KAF4, KAF3, KAF2 and KA mount lenses and features a 25.73MP CMOS sensor with a sensitivity up to ISO 1,600,000.  In addition to its photo capabilities, the K-3 mark III will record 4K video up to 30 frames per second and Full HD video at 60 frames per second.
Pentax developed a new optical viewfinder with a 100% frame coverage and a 1.05% magnification, making it unique in the market. Never before an APS-C body had the viewfinder characteristics of a full-frame camera.
The K-3 mark III also incorporates a totally redesigned mirror- and shutter-drive mechanisms, resulting in reduced mirror bounce and the possibility for higher speed mirror action.
At the back of the camera we find the 3.2” capacitive touchscreen with 1.62 million dots.

Other notable enhancements include UHS II memory card speeds, USB 3.2 with a Type C port, improved 101-point autofocus, a 307K-pixel metering system and burst shooting up to 12FPS.

The Pentax K-3 mark III comes with all other features Pentax is known for. It has got Pixel Shift resolution, a 5-axis Shake Reduction system that was improved to work up to 5.5 stops of compensation, Astrotracer support, GPS logging and more.

Pentax K-3 mark III – Technicals at a glance
Sensor Resolution 25.73 MP
6192 x 4128 effective pixels
Other Resolutions 15M (4752×3168), 9M, 2M
Sensor Size 23.3 x 15.5 mm (APS-C)
AA Filter No.
The AA filter can be simulated
via ultrasonic sensor vibrations
Super Resolution 15M (4752×3168), 9M, 2M
Sensor Size 23.3 x 15.5 mm (APS-C)
Sensor Resolution Yes, via Pixel Shift Resolution
Output pixel count unchanged
Dust Removal DR II ultrasonic
ISO Range 100-1.6M (1/3, 1/2 or full stops)
RAW Bit Depth 14
Shooting Modes Auto, P, Sv, Tv, Av, TAv, M, B, X, five user modes on mode dial
Shutter Speeds 30s-1/8000s (up to 20 minutes in Timed Bulb)
Stabilization 5-axis sensor shift
(up to 5.5 stops, works with any lens)
Light Meter 307K pixel RGB sensor
Meter Range -3 to 20 EV
Max Frame Rate (buffer) H: 12 fps (37 JPG, 32 RAW)
M: 7.0 fps (60 JPG, 37 RAW)
L: 2.5 fps (90 JPG, 39 RAW)
File Formats Stills: JPG, PEF (RAW), DNG (RAW), TIFF (in-camera development only)
Videos: MOV
AF System and Modes SAFOX 13: 101-point phase detect (25 cross-type)
AF Sensitivity -4 to 18 EV
Video Mode 4K: 30/24p
1080: 60/30/24pMPEG-4 AVC/H.264 (.MOV)Clips up to 4GB / 25 minutes
Video Sound * Built-in stereo microphone
* External stereo microphone input
Built-in Flash No
Flash Sync. 1/200 s
Hot Shoe Yes
Viewfinder Pentaprism, 100% coverage, 1.05x magnification

-4.0 to +1.0 diopter built-in

LCD 3.2-inch, 1620K dots
Weather Sealed Yes
Battery D-LI90 rechargeable
Media Slot(s) 2 SDXC / SDHC / SD
(slot 1: UHS-II compatible, slot 2: UHS-I)
Wireless Connectivity Yes, Wi-Fi (b/g/n) and Bluetooth 4.2 (Low Energy)
Connectivity USB 3.2 (type C), DC in, x-sync socket, HDMI output (type D),
IR port (front and rear), stereo microphone and headphones
Dimensions (WxHxD) 134.5 x 103.5 x 73.5 mm
Weight 735g (~820g with battery and SD card)

Photographers that are used to the regular button layout on Pentax DSLR’s will immediately notice the small joystick on the back of the camera. The AF points are no longer controlled by the 4-way pad, but are now controlled through that mini-joystick.
For me personally it’s a great improvement. Moving the focus points around goes much smoother and especially with moving subjects it’s much easier to place the focus points or focus group where you need them.

Following the Smart Function settings of the Pentax K-1 and KP, the K-3 mark III has further improved its capabilities and more importantly it’s customisability.
By pressing the S.Fn (smart function) dial on top you get access to 5 custom function positions. These 5 positions can be filled with your personal choice out of the 22 functions available on the Pentax K-3 mark III. If needed you can even deactivate certain functions to simplify the camera operation.
Currently my 5 function positions consist of:

  • E-dial
  • Active AF area
  • AE metering mode
  • Drive mode
  • White balance

As Pentax has done in the past, most functions are accessible by button and dial controls on the camera body itself. The mode dial has all the regular settings like Av, TAv, P, and no less than 5 user settings. Viewfinder operation, live view shooting and the movie record mode are selected by a dial on the top as well. As I’m used to with previous models, everything can be adjusted without the need to take the camera away from your eye.

The e-dial on top of the camera has in improved function as well. This new function lets you assign the desired function to the third dial (see image) — either ISO sensitivity or exposure compensation — for each exposure mode.
For instance, when you are shooting in M-mode, you can assign the ISO sensitivity function to the e-dial so you can use all three dials for the adjustment of the exposure-determining factors (shutter speed, aperture and ISO).
Or you can assign the exposure compensation function while you are photographing in Aperture priority mode. This new E-Dial function simplifies camera operations greatly.

Pentax K-3 mark III – In the field

Upon the arrival of the camera, I went through the entire menu to adjust a lot of it’s settings. Some features are turned off by default, but my preferences have grown on me over the years.
For example; I’m always shooting RAW files in the adobe RGB colour profile. My focus settings always have focus priority instead of shutter priority, the menu should be in a grey colour scheme and automatic horizon correction should be switched on. Of course, this list goes on and on and on….

The first trip with the camera was to an enormous flock of starlings that had their sleeping spot close to my house. An ideal spot to get familiar with the camera and fiddle a bit with ISO, focus settings and white balance.

To help me to get the most out of the improved UHS-II compatible SD-card slot, I used a Sandisk Extreme Pro SDXC II card with a 300 MB/s read speed, but more importantly a 260 MB’s write speed.

Pentax K-3 mark III
Pentax K-3 mark III - DFA* 70-200 @F4 - 1/1000s - ISO 800

The viewfinder, equipment and camera settings

In the weeks prior to my testing sessions, I heard a lot of positive news about the large and bright viewfinder. Truth be told….I was not that impressed at first. Untill it struck me; I was used to the large viewfinders of the full-frame Pentax K-1 and the medium format 645Z. Only when I went back home to compare it to my Pentax K-3 mark II I realised the improvement.
The viewing angle is now as wide as the Pentax K-1 and offers an exciting and clear view of your compositions. The improved glass of the pentaprism offers a wide, undistorted view of the world around you. I’m one of those photographers who prefers a real-world-view over the digital viewfinders found in mirrorless bodies so I can really appreciate this improvement that without a doubt will find it’s way to future generations of Pentax bodies as well.

During my first testing week, Holland was hit by a severe cold-front and the first day out in the field were challenging for both equipment and photographer.
The ice-cold wind (-15 degrees Celsius) in combination with a snow storm gave us beautiful surroundings but harsh conditions. The Pentax K-3 mark III was paired with my DFA* 24-70/2.8 and the DFA* 70-200/2.8 for that day. Due to the strong winds, working with a tripod was not really an option so all images were made handheld.

My preferred shooting style is in either Hyper Program or in Aperture priority mode and multi segment metering. The exposure for most of my images are corrected by using the exposure compensation button. In a white landscape, the first thing I tend to do is dial in +0.7 EV to create a true to reality white landscape. For the images with the horses, I had to go even further and they were mostly taken with +1.3 EV.
Because of the strong winds, steadying myself was an issue. Besides this hurdle, I was also working with moving subjects, I aimed for fast shutter speeds and used mainly ISO 400 and 800.

Pentax K3 mark III winter landscape
Pentax K-3 mark III - DFA* 24-70 @F6.3 - 1/4s - ISO 1600
Pentax K3 mark III winter dunes
Pentax K-3 mark III - DFA* 24-70 @F7.1 - 1/50s - ISO 800

Battery Life

I was out with the camera for most of the day and started with a full D-LI90 battery. Yes, that’s right, Pentax has kept the battery that they are using for over decade now so I was very pleased with that. As I often travel to remote places without access to electricity I have quite of few of this type lying around. So no need to buy a new set of spare batteries!
During the day I shot a little over 700 images and the camera was out of my camera bag and into the cold for most of the time. I must have made about 600 images before I needed to replace the battery. In the harsh and cold conditions I had, excellent results from the camera!

Pentax K3 mark III coot
Pentax K-3 mark III - DFA 150-450 @F6.3 - 1/800s - ISO 800

Camera controls

Due to the cold weather I was wearing gloves most of the time and as most of you know, controlling the camera is not always an easy task with gloves. I don’t have the fancy ones with removable finger tips, but the plain vanilla snowboard kind. Due to the placement and protruding knobs and dials I had no issue with changing settings. It helps of course that I’m used to the general layout and placement of the camera controls. Yet I’m confident that operating the camera will be breeze for most photographers. And let’s face it…. We rather point our attention to our subjects than at finding the buttons on our cameras.

Pentax K3 mark III high key
Pentax K-3 mark III - DFA* 70-200 @F3.5 - 1/1000s - ISO 800
Pentax K3 mark III silhouettes
Pentax K-3 mark III - DFA 150-450 @F10 - 1/800s - ISO 100

Weather sealing

Although I knew that there were only 5 Pentax K-3 mark III’s in the whole of Europe, I had utter confidence in the weather sealing of the camera. It was allowed to reach a temperature below freezing point and all the snow that was falling on top of it, was allowed to fall of naturally.
Actually, this wasn’t its first test. Remember the image with all the starlings in the sky? The definitely knew how to aim, as not only yours truly, but also the camera got hit by some bird droppings. Weather-sealing score? Top notch if you ask me!

Pentax K3 mark III kingfisher
Pentax K-3 mark III - DFA 150-450 @F7.1 - 1/250s - ISO 1250

Pentax K-3 mark III – Autofocus

Due to the mayor upgrade that Pentax gave the autofocus system, I’m dedicating a chapter this subject alone.  When you are working with your camera and when you working with moving subjects, you want a camera that switches on in an instant and is able to track the movements of your subject across your field of view.

The Pentax K-3 mark III features 101 autofocus points of which 41 are selectable by the 8-way joystick on the back of the camera. The focus points are placed close to the sides of your viewfinder allowing to select a wide portion of your composition, similar to mirrorless cameras.
The autofocus system makes use of the 307k RGB sensor to recognize subjects like birds, cars and eyes. It also features a deep learning technology that aids in recognizing subjects. This technique makes use of analysis of the colour distribution and shape detection.
The autofocus algorithm also had an upgrade to better cope with erratic moving subjects.
That’s all fine on paper, but how does it perform in the field?

My focus during these past weeks have mainly been wildlife as I was really looking forward to add a camera to my bag that would bring excellent autofocus to my available toolset.
And man was I blown away by its capabilities!
The camera turns on almost instantly and it will start searching for your subjects right away. It feels to me that it will find your subject within a split second. It’s highly responsive and gives you the confidence that it knows what it’s doing.
In my preferred autofocus settings, I select a small group of autofocus points that I move around in the frame depending on the composition that I need. With larger animals or humans, this group is placed at their heads. With birds and such I tend to place that group of autofocus points at the body. I’m operating the focus solely by the back button and I’ve set my priority for the subject to be in-focus instead of maintaining a high framerate.

Pentax K3 mark III goose
Pentax K-3 mark III - DFA 150-450 @F6.3 - 1/2500s - ISO 1600

During the first day, when my subjects were often partly obscured by snow, I found the focus to be snappy and instantly. Even abrupt and erratic movements were caught flawlessly by the camera. Placing the autofocus points on the right position in the frame was of course made easier by means of the large and bright viewfinder.

Earlier models of Pentax were always struggling with subjects that were moving towards you. More often than not, the field of sharpness was placed behind the eyes of these subjects. The ears and necks were often sharp and the eyes were out of focus. Needless to say, I did some tests in similar situations.
Was I in for a surprise. Image, after image, after image, was sharp in these sequences. I didn’t do the math, but with my settings I estimate that 90 to 95 percent of the images had perfect focus placement. Both a slower moving mountain biker and a fast-moving kite-surfer were tracked with equally successful focus accuracy.

The autofocus system has seen such a major upgrade that I’ve got no doubts in placing it at a similar level to top-end professional cameras from other brands. Not only the accuracy and responsiveness, but it also includes the greatly improved continuous tracking ability.

Pentax K3 mark III off the lip
Pentax K-3 mark III - DFA 150-450 @F6.3 - 1/2000s - ISO 800
Pentax K3 mark III waveboard
Pentax K-3 mark III - DFA 150-450 @F6.3 - 1/2000s - ISO 800

Autofocus sequence from a kite surfer at the Dutch “Zandmotor”

Pentax K-3 mark III – Using Legacy lenses

As I’ve become used to, Pentax keeps true to the tradition that a camera should be compatible with every K-mount lens ever build. In my personal collection there are some classics like the A* 200/4.0 macro, the A* 85/1.4 and the A* 135/1.8.
The large and bright viewfinder makes it much easier to perform the manual focus action than on the previous APS-C bodies. The camera notices that you’ve attached an all-manual lens and will ask you to input the focal length. That way the advanced 5.5 stop shake reduction will have the optimal effect on every lens ever build. What’s new is the addition of the possibility to manual set the aperture you’ve chosen to be included in the EXIF information.

When using these older lenses, such as M-series lenses or A-series lenses with a lens aperture ring, previous Pentax camera models provided automatic exposure setting with closed-down metering. This was done by pressing the green button in the manual-exposure mode.
The Pentax K-3 mark-III is designed to automatically perform closed-down metering at the moment of your shutter release. It now provides automatic exposure setting in the Av and TAv modes while the photographer sets the desired aperture using the lens aperture ring.
For me, the ability to use older glass is still one the feature that I cherish so much about the Pentax system.

Pentax K3 mark III lightpaint
Pentax K-3 mark III - DFA* 11-18 @F7.1 - 30s - ISO 400

Pentax K-3 mark III – Image quality

As stated earlier, I won’t get in too much detail about the image quality. I don’t have the means to test it on a technical level and I was using an early firmware on the camera.
But my personal observations are very favourable regarding the RAW output of the K-3 mark III. I’ve been shooting in the DNG-RAW format so I could open and edit the files in Adobe Photoshop. The ability open up the shadows in photoshop is there should you need it. Minimal colour-noise is introduced when you increase the exposure in post processing. For me an indication that the dynamic range is wide and a lot of information is recorded. At higher ISO’s it seems to outperform even the K-1 mark II. This is especially noticeable in the accurate display of the blacks in the image.

Pentax K3 mark III anemone
Pentax K-3 mark III - FA* 200 macro @F4 - multiple exposure - ISO 100
Pentax K3 mark III wood anemone
Pentax K-3 mark III - FA* 200 macro @F4 - multiple exposure - ISO 100

Pentax K-3 mark III – Final thoughts

Since the first mock-up of the Pentax K-3 mark III was shown during the 100 year anniversary of Pentax a lot of fine-tuning has been made to this camera. Pentax has done once again what it is known for: it has produced a flagship DSLR camera with a host of unique features. For the fans of DSLR camera’s the arrival of the K-3 mark III is great news.

Pentax was the original inventor of the Pentaprism. It’s used in DSLR’s all over the world and it’s still the only way for a photographer to have a real-world connection to your subjects. With the arrival of the mark III, Pentax has made further improvements to the pentaprism, giving APS-C users the feel of working with a full-frame camera.

The autofocus system has gone through a complete overhaul and it’s right there with the best professional cameras of competing brands. There have been a lot of complaints about the previous sports- and action capabilities of Pentax cameras, but I dare to say that Pentax will claim a spot in these disciplines with this camera. The greatly improved burst speed of 11 tot 12 frames per second will add to that experience.

I think that the Pentax K-3 mark III will claim it’s spot on the Pentax timeline of innovation. It’s development is another highlight like the 1954  first instant return mirror system, the 1957 first pentaprism, the 1971 first  TTL automatic-exposure control, the 1980 first trough-the-lens autofocus, the 2010 first digital medium format in the form of the Pentax 645D and the 2014 first above 100 score at DxO lab with the Pentax 645Z.

The highlights of the Pentax K-3 mark III

  • New 26.8 BSI megapixel sensor
  • Sensor shake reduction; 5.5 stops image stabilisation
  • 100% viewfinder with 1.05x magnification
  • Highly sensitive: ISO 100 to 1.600.000
  • 4K video modes
  • 101 AF points, 25 of those are cross-type
  • 2 inch TFT capacitive touch screen with 1.620.000 pixels
  • Up to 12 fps with continuous AF
  • 1/8000s shutter speed

If you want to stay in touch with future updates and images from me and Pentax K-3 mark III, please follow me on Instagram: @mycameratravels

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Comments (17)

Thanks for the review! It’s been a long wait, but it sounds like they used the time well. I concur about the extra thought given to improving the camera’s operability with legacy glass – I have many old K-mount lenses I still enjoy using. I look forward to trying the K3-III.

The greatly improved viewfinder, will no doubt make you love that old, manual focus glass even more!

Prima verhaal Mike, eindelijk weer eens mooi Pentax nieuws- inmiddels in 4 jaren toch wel verknocht geraakt aan die rare kleine KP trouwens, .

Dank je Hans, het is inderdaad een erg knap staaltje werk dat ze hebben afgeleverd. Hoewel hij in de K-3 lijn wordt uitgebracht voelt en werkt hij echt op een totaal hoger niveau. Ik was al fan en deze ontwikkeling maakt dat gevoel alleen maar sterker.

Mooi review Mike, je bent er vlot bij 😉

Ben reuze benieuwd hoe het in de praktijk uitpakt, autofocus verbeteringen klinken goed!

Er staat een zwarte op pre-order voor me bij Camera-NU 🙂


Hoi Jan,
Hij kwam inderdaad op precies het juiste moment. Net voor de mooie winterse dagen!
We gaan veel plezier hebben van deze flink verbeterde camera 🙂 Veel plezier er mee en ik zie je snel!

Nice review. I have a K-3II. Yeah, the autofocus is problematical for fast-moving objects. Fortunately, I usually use the camera for landscape and astrophotography, so that hasn’t been a huge problem.

Re the pentaprism, Pentax actually had the first roof pentaprism in a _Japanese_ SLR. Some German SLRs and an Italian SLR had such prisms years before them.

Thank you Alan, also for the addition to the text!
Best regards,

Hoi Mike,

very nice review, thank you for that. I saw that you used the FA 300 mm with screwdriver AF on the K3III. Can you recommend that? Did you also use the DA*300mm?
Guess the DA* is much snappier? Would appreciate a comment on that from you.

Cheers, Erhard

Hello Erhard,

That lens is actually the FA* 200/4.0 macro (which I use manual focus only). But the mark III works flawlesly with the DA* 300/4.0 as well, the sequence of the kitesurfer is made with that lens with the DA1.4x converter attached

Best regards,

Hi Mike, what are your autofocus settings on the K3 III for Birds/Sports/Action?

BR Erhard

This looks like an amazing action camera. As a Canon user I feel abandoned by Canon, they didn’t release any action camera under 2000 euro since 2014 (Canon 7D II).
Congratulation to Pentax.

Hello Cryssy, I understand your feelings. I think Pentax users will get a lot of camera at thi spricepoint. There are so many unique features in this body. Great step forward in the development of a new generation DSLR’s I think.

will the old screw dr f/fa*300 work well with the new autofocus system?

Dear Lee, I’ve tested it with the FA* 300/2.8 and that works flawlessly. I would think however that the newest generation SDM lenses are faster.

Hoi Mike,

Goede review, met nuttige en praktische info !
Ik ben nog wel even benieuwd Mike, welk merk en type tripod gebruik je ? En wat bevalt je daaraan in vergelijking met ander(e) merk(en) ?

En eventueel: welk filtersysteem en waarom die juist in vergelijking met andere merken ?

Dank je Marco, zelf werk ik nu alweer een aantal jaar met de Reporter en W-serie van Sirui. Binnenkort komt er een leuke video online waarin ik daar wat verder op inga, maar er staat ook al wat op deze pagina:

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