The K-01 feels solidly built and has some heft to it. It is almost as heavy as the Pentax K-r DSLR. The design is "boxy" but the camera nevertheless handles well overall and is visually extremely nice. In a few instances has the design negatively impacted useability. We will mention this as we come across it in the various sections of this review. The rubber cladding could indicate that the K-01 is weather sealed, but it is not.
The black parts of the body below are made of sturdy plastic ("polycarbonate"), the silver parts are metal, and the sides are made of rubber with plastic underneath. The K-01 doesn't have an underlying magnesium body like the K-5; the inside frame is made of aluminum.
The K-01 uses a 16.28 MP (effective) APS-C sized CMOS sensor from Sony. The sensor is much like the one in the Pentax K-5, if not the same, which bodes well for image quality. The is an anti-alias filter in front of the sensor and the outermost surface is coated to repel dust. The camera has a dust removal feature, which works by shaking the sensor. Dust removal can be initiated manually, or set to happen each time the camera is powered up or down, or both. As the K-01 uses the same (older) dust removal system as the K-x, K-r and earlier DSLRs, we believe that it is less effective than that of the K-7 and K-5, based on user reports and our own experience with those cameras.
The color depth is 12 bit in DNG RAW mode and 8 bit in JPG mode. The image size is 4928 x 3264 pixels when set to its highest resolution (at a 3:2 aspect ratio).
The effective size of the sensor is 23.7 x 15.7 mm which gives a "crop factor" of 1.5. In other words, a 20 mm lens on the K-01 has the same field of view as a 30 mm lens on a 24 x 36 mm (full-frame) camera. The sensor has an area that is 13 times larger than the sensor in Pentax's other mirror-less camera, the Pentax Q.
The K-01 has Pentax's in-body shake reduction, where the sensor is mounted on a plate which floats in a magnetic field. It works very well, at par with the K-5. The shake reduction works with all lenses, past and present. For older lenses you must enter the focal length manually into the camera for the shake reduction to function. F-series and newer lenses transfer this information to the camera without user intervention.
When the camera is turned off, the sensor is covered by the focal plane shutter like on any Pentax DSLR. As soon as you power up the camera the shutter opens to facilitate the live view image on the monitor. A mirrorless camera is therefore more prone to sensor dust than a DSLR used with the optical viewfinder.
The K-01 powered off and thus with the shutter closed
When the shutter button is pressed fully, the shutter closes and then opens for image capture for the exposure duration set, for example 1/125th of a second. Once the image is captured, the shutter closes and re-opens once again to allow the live view image to be presented on the monitor. There is thus quite some shutter activity for each exposure and the camera's operation is not as quiet as we had expected or would have liked. This behavior is similar to that of DSLRs in live view, though of course, there's no mirror moving around on top of the shutter.
Just like on the current Pentax DSLRs, the K-01's shutter lag is minimal.
The Pentax K-01 has a KAF2 lens mount. This is a variant of the original K-mount which Pentax introduced back in 1975. The KAF2 mount on the K-01 has some restrictions which we will explain later. Even then the K-01's mount is compatible with all Pentax bayonet lenses for the APS-C or 35mm film format. With the appropriate adapters, M42 screw mount lenses can be used, and so can Pentax lenses for the 6x7 and 645 formats. It is a strong point in favor of this camera that a huge amount of lenses are readily available unlike some other mirrorless cameras where only a few lenses are available. Check out the PentaxForums lens database for lens availability.
Compared to the original KAF2 mount the mount on the K-01 has two restrictions:
The lens release button has been designed nicely into the body.
The Pentax K-01 has no viewfinder and none is available as an accessory. This leaves the LCD monitor as the only option for composing the image. There is no top LCD either, so the monitor is also used for setting all shooting parameters.
The monitor is 3 inches in size diagonally and has VGA resolution (921,000 dots). It is bright with an excellent color rendition. The color balance can be finely adjusted. But how does it fare as a replacement for a viewfinder?
Outdoors in strong sun-light can be a challenge, at least here in the extreme light in Arizona where this review was made. It helps to turn off the display of shooting information since it makes it easier to identify the edge of the monitor which is essential for accurate image composition. Interestingly, we had most difficulties in backlit situations where the monitor produces a strong mirror effect reflecting an image of the photographer! The monitor is useable in bright light, but not great. It is a tad better than the Pentax Q's monitor which was impossible to use under similar conditions.
Mounting the camera on a tripod helps since it frees up a hand to cast some shade on the monitor.
Besides image composing, you may also need the monitor for focusing in case you use non-autofocus lenses, or if you just want to verify focus with an AF lens. Here the "focus peak" and "focus zoom" features come to the rescue. Focus peak displays exaggerated bright edges around the subject in focus and these edges ares easy enough to see even outdoors in bright light. Focus zoom magnifies the area and is also a good help. With manual focus lenses one press of the OK button enlarges the image 2x and makes the focus peak outlines really stand out.
LCD monitor shades are available in various styles. Some attach to the tripod mount, some attach through suction like the Hoodman shown here. A shade like this could be a convenient remedy in strong light. We would, however, much prefer that the K-01 either had a built-in or an accessory electronic viewfinder.
In dim sunlight, cloudy weather and indoors there is of course no problem at all using the monitor as viewfinder..
In the traditional Pentax style the lettering in the menus and the icons in the control panel are large and clear and thus quite visible so even in bright light it is possible to change settings using the LCD monitor.
The monitor is fixed but is viewable from wide angles and we didn't miss the lack of a tilt/swivel monitor for ordinary picture taking. However, a tilting electronic viewfinder would be welcome in particular for macro work done close to the ground.
Concluding, we hope that Pentax would decide to develop an EVF, but that appears to not be in their plans.
The K-01 takes all three types of SD cards, SD, SDHC and SDXC. We used a Transcend 32GB class 10 card during our tests. It is inexpensive and it worked flawlessly.
The SD card slot is located behind double doors. First a part of the rubber cladding must be opened, then a hinged battery door. The door opens 180 degrees which makes it very easy to grab the card and pull it out. Fortunately the card doesn't "stick" as is the norm on the K-7 and K-5. While it is very easy to open the SD card door, the rubber cladding takes some practice to open and in particular to put back. This is one of the minor annoyances where design took priority over function.
The included rechargeable lithium-ion battery is rated at 1,860mAh and is the same battery as used in the K-7, K-5 and 645D. With the K-01, however, we experienced that the battery lasts significantly shorter than with the K-5. It became evident in our field test where we used the two cameras side by side. This is confirmed by Pentax's specifications, which states 500 shots for the K-01 and 980 shots for the K-5 on a full charge with no use of flash.
With a battery life on the short side we recommend that you spring for one or two spare batteries.
The battery door is easy to open and off to the side. as shown to the right, even with a good sized tripod mounting plate in place the battery can be exchanged without removing the camera from the tripod.
As is usually the case on a Pentax, the tripod socket is aligned with the optical axis and made of metal so you don't risk to strip the threads.
Two of the electrical connections (HDMI and USB/AV out) are located behind the same rubber door that covers the SD card door.
The connection for an external stereo microphone is placed on the opposite end behind a small rubber flap.
AC power is connected in the battery chamber with a dedicated battery-like connector.
There is not much of a grip; it is basically just a bulge. But in combination with the rubber surface it feels just right and one handed shooting is possible with lenses like the 40mm lens and the 18-55mm zoom lens. The camera is almost the size of an entry level DSLR which works much better in connection with larger lenses than the more smallish APS-C or four-thirds format mirrorless cameras from other manufactures. A dedicated battery grip would have made the K-01 even easier to hold (especially for verticals), though offering such an accessory for a mirrorless camera could be considered a stretch, as it goes against the compact design goal for mirrorless cameras.
Compared to the K-7 (K-5) one appreciates how much more compact the K-01 is:
All buttons and dials essential for shooting are on the right hand side within easy reach of the thumb and index finger except for the green button which is hard to reach without shifting the position of the hand. This is somewhat unfortunate in particular for users of legacy lenses like the K and M series, which require stop down metering with the green button. This bad placement of the green button is the second of the two issues we found where design won over function. It would have been better had the green button and the play button been swapped.
The single e-dial and the exposure mode dial offer confidence resistance inspiring resistance between the click stops. It is thus not possible to accidentally knock these dials into the next position.
The AF/MF switch is a convenient sliding switch found in the usual place on the left side. This sliding switch is much more convenient to use than the rotating knob on the K-5.
It's a shame that the power button doesn't support DOF preview as the K-5 does; the red or green button must be re-mapped in order to support this. This is just like on the K-r.
As pictured above, big lenses, such as the F* 250-600mm F5.6, can be used with the K-01. The only issue when mounted on a tripod is that the AF isn't stellar, and that the screen can be hard to see at times. You'll notice this trend with most long telephoto lenses, as they're simply not meant for use with CDAF.
The K-01 has a built in flash as well as a standard hot shoe compatible with Pentax' line of flashes and extension cords. With an F-series or newer lens and a flash with a zoom head (AF360FGZ and AF540FGZ) the flash will adapt the angle of light output to the focal length of the lens.
In Auto exposure mode and in some of the scene modes the built in flash pops up automatically. In other modes you pop it up manually. Even though the flash is raised some distance from the optical axis there is a risk for red eye effect and the lens hood on longer lenses may cast a shade and should be removed.
The flash can be set to always fire, to fire only when needed, or to never fire. Red-eye reduction, slow speed synchronization, rear curtain synchronization, and flash exposure compensation are also available.
Pentax and Marc Newson got most things right. The camera handles well, has a convenient size and heft, and most buttons and all dials are placed within reach when shooting.
The only major issues are 1) the green button is placed out of reach when the camera is held in shooting mode, and 2) the lack of an electronic viewfinder. The rubber covers are fiddly but only until you get the hang of how to handle them.