Pentax K-1 Technical Info

by Mike Tomkins | Posted: 02/18/2016

Body

The Pentax K-1 sports a brand-new, weather-sealed body constructed from magnesium alloy. It's comprehensively weatherproofed, with a total of 87 seals protecting seams, compartments and controls alike from ingress of dust or moisture. And if you purchase the optional portrait / battery grip, this has a further 47 seals. Of course, you'll also need to be using a weather-sealed lens for proper protection.

To choose a weather-sealed lens, look for either the AW or WR designation on a full-frame or sub-frame optic / rear converter, or the DA* designation indicating a premium sub-frame optic. (All of the latter are weather-sealed, but note that the same is not true of FA*-badged lenses.) Continuing the weather-sealed system, the Pentax AF360FGZ II and AF540FGZ II flash strobes are also weather-sealed, as is the O-RC1 remote control.

As well as dust and water-resistance, the Pentax K-1 is also freezeproof, able to operate in temperatures as low as 14°F (-10°C).

Sensor

At the heart of the Pentax K-1 is a 36.4-megapixel full-frame CMOS image sensor with a Bayer RGBG color filter array. Dimensions are 35.9 x 24mm, total resolution is 36.77 megapixels, and the pixel pitch is 4.9 microns. Maximum image size is 7,360 x 4,912 pixels, except when operating in the APS-C crop mode, when resolution tops out at 4,800 x 3,200 pixels (or in other words, 15.3-megapixels).

As with other Pentax DSLRs since the K-3, the Pentax K-1 doesn't include an optical low-pass filter. It does, however, feature an on-demand mechanical antialiasing function. More on that in a moment. (Or read Dave Etchells' "Geek's Guide to On-Demand Low-Pass Filtering" from our Pentax K-3 review for the full story; the feature is unchanged from that camera.)

Processor

In place of the PRIME III image processor used in the K-3 cameras, the Pentax K-1 opts instead for Ricoh's new PRIME IV processor. (That's a contraction of "Pentax Real IMage Engine", if you're curious.)

Ricoh hasn't stated what performance gains or other tweaks are to be found in the newer variant of the processor, and nor can any obvious conclusions be drawn from the camera's burst-capture performance. (Maximum throughput tops out at around 160MB/second, vs. around 200MB/second for the earlier, sub-frame Pentax K-3.) Likely the sensor itself is the limiting factor here, though, rather than the processor.

Sensitivity

Like the medium-format Pentax 645Z, the K-1 has an overall sensitivity range of ISO 100 to 204,800 equivalents. That's a significantly more generous range than the 100 to 51,200-equivalents of the sub-frame K-3 and K-3 II. The entire range is available without needing to enable ISO expansion, and step sizes of 1/3, 1/2, or 1EV are available.

There's also an Auto ISO sensitivity function, whose upper limit can be manually selected. And as in past cameras, you can configure the Pentax K-1 to raise sensitivity more or less quickly than the default.

Performance

With a larger, higher-resolution sensor than its sub-frame siblings, the Pentax K-1 understandably trails them in terms of burst-shooting performance. With a manufacturer rating of 4.4 frames per second, it also sits just slightly behind the competing Nikon D810, Canon EOS 5DS R and Sony Alpha A7R, all of which are manufacturer-rated at five fps.

However, it's worth noting that all three are also significantly more expensive cameras. A fairer comparison would be to the similarly-priced Sony A7R, which also has similar resolution -- and here the toss-up falls in Ricoh's favor. Sony rates the A7R for around four fps, making the K-1 about 10% faster than its nearest rival.

Of course, one should also note that all of this relates to full-sensor capture. If you apply an APS-C sensor crop, the Pentax K-1 is capable of shooting at around 6.5 frames per second.

And although it won't knock your socks off for performance, the buffer depth is pretty generous in either mode. The full-resolution mode can capture around 70 JPEG or 17 raw frames in a burst, while the APS-C mode will allow up to 100 JPEG or 50 raw frames in a burst.

There are also two reduced-speed burst shooting rates available, although the rate for the minimum-speed option differs depending on crop mode. The intermediate rate provides three fps regardless of crop mode setting, while the lowest rate should manage around 0.7 35mm frames or one APS-C frame per second. Either option should prove handy for situations where you don't need the full burst rate, but you're still shooting faster than you'd want to by rapidly pressing the shutter button. (Although we'd still like to see the ability to manually dial in your own chosen burst speed for reduced-rate capture.)

As you'd expect, the lower-speed burst modes have even greater burst depths. For full-frame shooting, Ricoh claims a depth of 100 JPEG or 20 raw images at three fps, or 100 raw / JPEG images at 0.7 fps. Crop to APS-C, and the company predicts a depth of 100 JPEG or 70 raw images at three fps, or 100 raw / JPEG images at one frame per second.

(We're guessing that you'll actually get more than 100 frames here, and that Ricoh simply doesn't supply a precise value if more than 100 frames are possible.)

Shake reduction

Like the company's sub-frame DSLRs, the Pentax K-1 includes in-body image stabilization. It's a more sophisticated system than that in the APS-C flagship K-3 cameras, though. Where they were limited to three-axis Shake Reduction and had a maximum correction of around 4.5 stops to CIPA testing standards, the Pentax K-1 now offers up five-axis stabilization and a five-stop corrective range.

Wondering what the five different correction axes are? Wonder no more: The Pentax K-1 can correct for vertical and horizontal translational motion (that is, straight side-to-side and up-or-down motion), as well as for side-to-side roll, front-to-back yaw, and rotation around the central axis of the lens.

As in the Pentax K-3 II, the full-frame K-1 also includes a panning detection function. This determines that you're panning to follow a moving subject, and then automatically ceases its attempt to stabilize motion on that axis but still stabilizes the other axes.

Pixel Shift Resolution

Pentax had big news for still-life shooters and anybody else with static subjects when it launched the K-3 II last year: The brand-new Pixel Shift Resolution function, which we covered in quite some detail on our news page. The function is retained for the even higher-resolution K-1 with one important tweak. We'll give you the nutshell overview here; hit the link above for a more detailed analysis.

Pixel Shift Resolution has some similarities to -- and some key differences from -- the High Res Mode introduced by Olympus in the OM-D E-M5 II compact system camera. Like that system, Ricoh's Pixel Shift Resolution mode combines multiple sequential images with very slight adjustments of the image sensor position to create a single output image of higher quality.

Where Pentax's approach differs is that it takes four shots with full-pixel steps instead of eight shots with half-pixel steps, and it outputs each image at the sensor resolution, rather than at a significantly higher resolution. The downside is that there's likely more scope to improve detail using Olympus' methodology, but the upside is that file sizes can be much smaller the way Ricoh is doing things, and there's less time and processing power expended, too.

And while the output resolution is no different to that of a standard, single-shot image, there's little question that by getting full color information at every pixel, Ricoh can still significantly improve detail. (You only need to look at images from the Foveon X3 sensor-based cameras from Sigma, which actually record full color at every pixel in a single shot, to see that.)

Nor is it just improved detail and a reduced incidence of moiré, false color and jaggies that makes the Pixel Shift Resolution function worthwhile. It also reduces image noise and yields a finer-grained noise structure, since the additive exposures for each pixel can be used to average out luminance noise, and the remaining noise isn't interpolated outwards to surrounding pixels.

So what's new in the Pentax K-1's Pixel Shift Resolution function? Well, formerly in the K-3 II, it only worked for completely static, tripod-mounted images shot with an electronic shutter. In our K-3 II field test, we described a potential workaround if you were shooting in raw format, and found that part of your image had moved subtly between frames, but now the Pentax K-1 should be able to deal with just such a situation by itself.

In essence, what the camera's doing is much the same as what we did in our K-3 II review: Look for areas that showed subject motion between frames, and then simply skip the Pixel Shift Resolution processing for those image areas. Since these subjects are moving, they're not likely to benefit noticeably from increased color resolution anyway, but it can still be applied elsewhere to static image areas.

On-demand low-pass filtering

When Ricoh launched the original K-3, it debuted a revolutionary new way of combating moiré, false color, and jaggies when needed, yet maximizing sharpness the rest of the time. Instead of the resolution-robbing optical low pass filter used by some cameras, Ricoh achieved the same thing with a very fine motion of the image stabilization system during exposure.

For those who want to know the nuts and bolts, the Anti-Aliasing Filter Simulator function is explained in detail by IR publisher Dave Etchells in our "Geek's Guide to On-Demand Low-Pass Filtering", part of our Pentax K-3 review. If you're already familiar with the system, which has since appeared in several Pentax SLRs, you know everything you need to about how it works in the K-1.

We should note, though, that since our review of the K-3, a competing technology has appeared on the scene. Sony's fixed-lens RX1R Mark II uses liquid crystal technology with conventional low-pass filter elements to permit low-pass filtration to be turned on or off completely, or to be set somewhere in between the two states.

And since it does so in hardware, it doesn't have the limitations of Ricoh's system, which reaches its limits at exposures of 1/1,000 second or faster. Beyond that point, you'll find that the strength of the AA filter simulator effect is diminished regardless of your settings. Also, Ricoh's system won't work with flash exposures, because the brief moment of illumination from your strobe isn't long enough for the required motion to take place. If you want to take advantage of the AA Filter Simulator to avoid artifacts in the studio, you'll need to use hot lights or available light.

Still, even in the face of what's potentially a better rival -- albeit not one available yet in an interchangeable-lens camera -- the importance of Ricoh's system for your photography can't be overstated. It places control back in your hands for most shooting situations, letting you decide what's most important for you on any given shot: maximum image detail, or resistance to objectionable artifacts.

Lens mount

The Pentax K-1's K_AF2 lens mount is a variant of the K-mount that has been used in all sub-frame Pentax digital SLRs to date, as well as the K-01 mirrorless camera. But where previous Pentax DSLRs (other than the medium-format 645-series, anyway) have been limited to using the centermost area of the image circle for full-frame optics, the Pentax K-1 will finally allow you to use your full-frame lenses as their designers intended. That's huge news, and it's the reason so many photographers have been asking for just such a camera from Ricoh.

In all, there are a dozen different full-frame lenses currently available from Pentax, or slated to ship in the not-too-distant future. And if you have an older Pentax full-frame lens -- or a lens that can be adapted to the Pentax K-mount -- you should be able to use that too.

When shooting with a sub-frame lens, the Pentax K-1 can detect this and automatically apply the requisite APS-C crop. Alternatively, you can make the choice to switch between full-frame and sub-frame operation yourself.

Dust removal

If you regularly change lenses -- or use consumer-grade glass that sucks air in and blows it back out every time you rack the focus or zoom -- you can expect dust to get inside your camera sooner or later. (Most likely, sooner.)

Ricoh has retained the same DR II dust removal system used in other recent flagship models for the new Pentax K-1. It uses a piezoelectric element that vibrates at higher frequencies than a sensor shift system can, and in our experience systems like these typically do a better job of shaking free dust that's stuck to the sensor's protective cover glass.

To help you decide when a more detailed cleaning is needed, the Pentax K-1 also retains its predecessors' dust alert function, which helps you to locate stubborn dust particles on the sensor for manual cleaning.

Lens correction

Also like other recent Pentax DSLRs, the Pentax K-1 includes lens correction functionality. This can correct for lens distortion, lateral chromatic aberration, vignetting and diffraction in-camera when using DA and DFA lenses, as well as with certain FA lenses.

Metering

The Pentax K-1 features an 86,000 pixel RGB CCD metering sensor. It has a wide working range of -3 to 20 EV with a 50mm f/1.4 lens at ISO 100. Metering modes on offer include Multi-segment, Center-weighted and Spot, and an exposure lock function is available, accessed with the AE-L button at the top right corner of the camera.

You can also specify up to +/-5EV of exposure compensation, or bracket two, three or five exposures with up to 2EV between exposures. For either compensation or bracketing, you can specify your adjustment in 1/3 or 1/2 EV steps.

And since the metering sensor is based around a color-filtered chip, it can also recognize color information, allowing it to help out with subject identification too.

Autofocus

The Pentax K-1 debuts a new 33-point autofocus sensor which is more point-rich than those found in earlier models. Dubbed SAFOX 12, it has much the same arrangement as the earlier SAFOX 11 design, but places an additional three AF points on either side of the main array, just inside the two linear AF points at the leftmost and rightmost ends of the array.

The 25 central points in a 5x5 array are all cross-types, sensitive to detail in both the horizontal and vertical axes. The remaining eight points, located towards the far left and right of the array, are linear points sensitive on just one axis. The centermost sensor as well as the points directly above and below it are precision points, capable of focusing with an f/2.8 aperture. These same points also have a working range of -3 to +18EV.

Autofocus mode choices include AF-S (single-servo), AF-C (continuous-servo), and automatic selection (AF-A). You can also switch from the default 33-point auto selection, with provision for Spot, Select, Small / Medium / Large expanded area or zone-select modes. For single-servo autofocus, Select allows only a single point to be chosen, rather than the fixed center point of Spot AF. Zone Select is similar, but allows a nine-point area to be selected, with the camera making the final determination of which points to use. Finally, Expanded Area works only in continuous-servo mode, and allows you to select a 3x3 array, a 5x5 array, or the entire AF array. Focus starts from the center point, but will be tracked anywhere within your selected array.

As in the K-3 cameras, Ricoh has included an autofocus hold setting for use in tracking, which will let you control how quickly the camera will react to a radical change in detected subject distance, such as you might get when shooting through a fence, or if somebody walked between camera and subject. You have four options: either the change will be near-instant with Hold AF Status set to off, or you can choose one of three durations (Low, Medium or High) after which the change in focus will be made.

You can also define whether a focus lock or a full shutter button press should be of greater importance to the Pentax K-1. In single-servo mode, you can choose focus priority to have the camera wait to trip the shutter until a focus lock is achieved, or shutter priority to take it as soon as you full press the shutter button. In continuous or AF-A modes, you can opt for focus priority, or frame rate priority (which takes another photo as soon as the shutter has recycled and there is available buffer space to do so).

Of course, all of the above applies only when focusing using the dedicated AF sensor, which can only happen when the reflex mirror is lowered. In live view or movie modes, the Pentax K-1 instead switches solely to contrast-detection autofocus, which provides both face detection and tracking capabilities. You can focus manually as well, just as you'd expect, and if you do so in live view mode there's a focus peaking display to help you ascertain the exact point of focus.

Flash

As you'd probably expect on a camera aimed at enthusiast or professional use, the Pentax K-1 lacks a built-in flash strobe. Many -- perhaps even most -- potential K-1 owners will see this as a good thing, since popup strobes represent a potential point of failure. If you're the type to rely on your popup strobe, though, you'll want to retrain yourself to bring a separate flash. Although with that said, the extremely wide sensitivity range of the K-1 should go some way to preventing the need for a flash in the first place.

If you're a fan of off-camera wireless flash, the absence of the built-in strobe also means that you'll need an extra external strobe, since there's no longer a built-in strobe with which for the camera body to communicate with off-camera strobes. (Of course, you could also use a wired tether between camera and strobe, using the K-1's sync connector or a hot-shoe mounted cable.)

Speaking of which, the standard hot shoe on the top deck also includes both support for a locking pin, and intelligent connections that allow for Pentax's P-TTL flash metering system. And the aforementioned PC sync socket is protected by a small, screw-in cap, although it isn't attached to the camera body, so you'll want to ensure it's snug so as not to lose it. Still, it's nice to have the terminal at all -- many competitors force you to buy a hot shoe to PC terminal adapter, if you want to hook up your studio strobes.

In-camera GPS

Like the Pentax K-3 II before it, the Pentax K-1 features a built-in GPS receiver, electronic compass and three-axis orientation sensor. Together, these allow it to geotag your images with their capture location, the direction the camera was pointing, and the extremely accurate time provided by the GPS satellites.

The K-1 can also record track logs in the KML format used by Google Earth, logging your location at intervals of 5, 10, 15, 30 or 60 seconds, with a duration of up to 9 hours at the minimum interval or 18 hours with a 10-second interval. (Bear in mind, though, that if you take advantage of the full duration, you won't have any battery life left over for shooting photos, which rather defeats the purpose of having the camera in the first place!) Regardless of the interval set, the maximum logging time is 24 hours.

Of course, we live in a world where there are now multiple competing standard for satellite positioning systems, and so when one refers to GPS, it isn't immediately clear which systems the device is compatible with. For the Pentax K-3 II, it's compatible with the United States government's GPS system, but not other systems such as Russia's GLONASS, China's Beidou, Europe's Galileo or India's IRNSS. That doesn't mean it can't get a fix in these regions, though, as GPS has pretty-much global coverage -- it just means that it can't take advantage of the extra satellites from the rival systems to gain a faster, more accurate fix.

What it can do, though, is to improve the quality of its positioning using a number of augmentations to the GPS system. These include the US Federal Aviation Administration's WAAS in North America, the European Union's EGNOS inside Western Europe, India's GAGAN within the Indian subcontinent, and both the MSAS and proposed QZSS systems within Japan. In other regions, the Pentax K-1 will fall back to relying solely on the base GPS system for its location information.

And AstroTracer, too

Nor is that all. If you've ever tried to shoot an image of the night sky to reveal the details invisible to the naked eye, you'll appreciate another clever capability of the Pentax K-1. It's something that, to date, has required an extra accessory on all but the K-3 II, and now the K-1 can manage it in-camera too.

By combining information from the GPS receiver, compass, orientation sensors and lens, the Pentax K-1 can determine how quickly stars will be moving across the night sky, and in which direction. It can then use the Shake Reduction system to counteract their motion, allowing for much longer exposures than would normally be possible without causing star trails to form.

The result is that you can get better results as an astrophotographer, without the need for any accessory beyond a good, sturdy tripod. The actual exposure time you'll be able to achieve will depend on the focal length of the lens you're using, and of course you won't be able to include foreground subjects without blurring them instead, but this function -- dubbed AstroTracer -- really is unique, and with its larger, more sensitive sensor and higher resolution, it shows even more potential on the K-1 than it did on the K-3 II.

Viewfinder

Ricoh has designed a new pentaprism viewfinder for the Pentax K-1, sporting an accurate manufacturer-rated 100% coverage. In place of the LED focus point indication used in earlier models, it now features an illuminated LCD overlay providing a customizable grid display, an indication of the crop area if applicable, and a dual-axis level gauge display.

Magnification is 0.7x (50mm f/1.4 lens at infinity), and the eyepoint is 20.6mm from the eyepiece frame, or 21.7mm from the viewfinder lens. The viewfinder comes with a Natural Bright-Matte III type focusing screen, and this is not interchangeable. The dioptric adjustment range of -3.5 to +1.2m^-1 is even broader than that provided in the company's flagship APS-C cameras.

Monitor

The Pentax K-1's rear-panel LCD monitor has probably the most unusual articulation mechanism we've seen to date, dubbed "Cross-Tilt". The monitor itself sits atop four struts which allow it not only to be angled to face up, down, left or right, but even swiveled somewhat. These struts provide for +/-35 degrees of side-to-side adjustment, and +/-44 degrees of vertical tilt.

Once they reach their maximum extent, a secondary hinge allows the screen tilt to continue upwards to the 90-degree position for waist-level or low-to-the-ground shots. It's a bit tricky to describe, but certainly provides a much wider range of motion than competing designs.

Of course, it can't be angled forwards for selfie shooting, but that's hardly a major use case for a full-frame camera. The one obvious downside compared to a more traditional tilt/swivel mechanism is that the display can't be closed facing inwards for added protection.

The display itself has a 3.2-inch diagonal, a 3:2 aspect ratio, and a total dot count of around 1037k dots. And helping combat glare and low contrast, the monitor has a gapless design. Further assisting with the visibility is a new outdoor view setting which boosts brightness with two-step control. And you can also dim the LCD significantly for night shooting, to help protect your night vision. Additional controls let you tweak brightness, saturation and color.

Top-deck Info LCD

For quick at-a-glance checks of basic setup, battery life and shots remaining, there's still a monochrome info display on the top deck. It's significantly smaller and contains less information than that on the earlier K-series flagships, helping to free up room for some of the new top-deck controls, but still hits the high points. For nighttime viewing, it has an amber backlight which illuminates when you press the dedicated lamp button on the top of the camera.

On-demand body lighting, too

That's not the only function of the lamp button, though. It also activates another unique feature of the Pentax K-1. On the outside of the body are an array of lights, but unlike those on the entry-level Pentax K-S1, these are no mere fashion accent. Instead, they illuminate the camera body to help make it easier to see what you're doing when fiddling with controls, changing lenses and so forth after dark.

One such LED sits beneath the pentaprism assembly on the front of the camera, providing illumination for the lens mount. Four more can be found on the rear of the LCD monitor, and light up the rear-panel controls once the display is tipped or pulled outwards from the camera body. Further LEDs cast some light on the K-1's flash card slots and cable connectors.

If you want, you can adjust the brightness of the LEDs or disable them altogether, as well. It's a really nice detail which makes it much easier to handle the K-1 at night. Hindsight is 20/20, but we can't help wondering why nobody thought of this before now.

Exposure modes

The Pentax K-1 offers a healthy selection of exposure modes. As well as Automatic, Program (with program shift), Shutter priority (Tv), Aperture priority (Av), Manual, and Bulb, there are a couple of Pentax exclusives: Sensitivity priority (Sv), and Shutter-and-Aperture priority (TAv). In these latter two modes, you can either dial in a sensitivity and let the camera select aperture and shutter speed, or dial in the aperture and shutter speed, then let the camera select the sensitivity. There's also a Flash X-Sync mode, which locks the shutter speed at 1/200 second, just a little faster than the 1/180 second typical of Pentax DSLRs.

There are also five separate User modes (U1 thru U5), allowing you to quickly recall settings groups you'd saved for particular shooting situations. And you can opt for various program lines when using automatic or semi-automatic exposure. As well as the default program line, you can bias the camera in favor of higher shutter speeds, a shallow or deep depth of field, or towards the MTF sweet spot of the lens.

Finally, the Auto mode now has an updated Real-Time Scene Analysis system which should provide better results when shooting in the Auto Select custom image mode.

Drive modes

Drive mode options in the Pentax K-1 include continuous (high, medium, or low), self-timer (two or 12 second), remote control (instant, three second, or continuous), bracketing, mirror lockup, HDR, interval, interval composite and multiple exposure. (More on these last few in the creative section below.) The bracketing mode allows 2, 3, or 5 shots with up to 2EV between exposures.

Shutter

The Pentax K-1's shutter speed range is unchanged from that of other recent flagships, but the shutter mechanism itself is new. It has a rated lifetime of 300,000 cycles, 50% higher than that of Pentax's APS-C flagships. Available shutter speeds range from 1/8,000 to 30 seconds in 1/3 or 1/2 EV steps, plus bulb.

White balance

The Pentax K-1's white balance system offers a wide range of options, including an interesting Multi Auto WB mode which aims to neutralize color casts from multiple different light sources in the same scene. As well as Automatic and Manual modes, the K-1 provides nine white balance presets (Daylight, Shade, Cloudy, Daylight Color Fluorescent, Daylight White Fluorescent, Cool White Fluorescent, Warm White Fluorescent, Tungsten, and Color Temperature Enhancement). This last option is used to retain and enhance the lighting tone - for example, to enhance a sunset.

White balance can also be measured from a neutral target, or a specific color temperature can be dialed in manually, using either Kelvin or Mired values. Three custom white balance values of each type can be stored in-camera. And finally, you can adjust white balance within a +/- 7-step range on both amber-blue and green-magenta axes.

Creative

The Pentax K-1 has a healthy selection of creative options. We've already briefly mentioned a couple: HDR mode and multiple-exposure shooting.

HDR mode captures multiple images, then microaligns them in camera and blends them to create a single image with greater dynamic range. You have a choice of automatic blending, or one of three effect strengths. These range from fairly natural to a bolder, crunchier feel. (And since the images are microaligned, the mode can be used handheld.)

And unusually, the mode even allows you to output a raw image, although much third-party software is unlikely to recognize that there are multiple shots in the file. (But you can split the HDR raw into three non-HDR raws using Ricoh's Silkypix-based bundled software, allowing you to tweak the results in your own HDR app.)

Multiple exposure mode also allows you to save your result as a single raw image merged from multiple exposures. There are three methods of merging the source images: additive, average or bright mode. The first two are self-explanatory, while the third takes the brightest pixel at any given location in the source images, and uses that in the final image. You can merge up to 2,000 frames, allowing for some pretty cool effects.

There's also a time-lapse function, which allows shots at 2-second to 24-hour intervals. Again, you can capture as many as 2,000 shots in a series.

Custom image modes include Auto Select, Bright, Natural, Portrait, Landscape, Vibrant, Radiant, Muted, Flat, Bleach Bypass, Reversal Film, Monochrome and Cross Processing. (Both Auto Select and Flat are new additions for the K-1.) Digital filters include Extract Color, Replace Color, Toy Camera, Retro, High Contrast, Shading, Invert Color, Unicolor Bold and Bold Monochrome.

And of course, there's the Pixel Shift Resolution function which we covered previously.

Copyright tagging

Like the flagship models which precede it, the Pentax K-1 can optionally embed copyright data into its raw and JPEG image files. You can enter both a photographer and copyright holder name from the camera body, and the headers of images will be tagged with both. It's not a permanent tag, and so you can't rely on it to protect your images from copyright theft, but it does make it so that you can easily identify who shot a particular image in your library.

Dual-axis level gauge

The Pentax K-1 features a dual-axis level gauge function. This detects both side-to-side roll, and front-to-back pitch. Both of these are displayed in the viewfinder and on the rear LCD.

Horizon correction

Ricoh goes a step further than most DSLRs, which simply show the degree of side-to-side roll, though. The Pentax K-1 can automatically correct for up to two degrees of roll in either direction if Shake Reduction is disabled, or one degree if it's enabled. If you're driven to distraction by tilted horizons, it's a great feature to have.

Composition correction

Horizon correction takes advantage of Pentax's sensor-shift system, and so to does composition correction. This is handy when you're shooting on a tripod, and want to make very slight adjustments to composition. You can move the sensor left, right, up, or down, and rotate it by up to a couple of degrees, fine-tuning your composition to perfection.

Movie capture

The Pentax K-1's Movie mode isn't as comprehensive as that of some rivals, but does hit the high points, making it reasonably suitable to grabbing short clips to accompany your stills. Standard movies are stored using MPEG-4 AVC / H.264 compression in a .MOV container, while interval movies, which we'll come to in a second, are shot with Motion JPEG compression.

The Pentax K-1 captures movies at up to Full HD (1,920 x 1,080 pixel; 1080p/i) resolutions, with a selection of frame rates include interlaced 60i / 50i or progressive-scan 30p / 25p / 24p at Full HD resolution. At the lower 720p resolution, you'll find a choice of progressive scan 60p / 50p rates.

Movies can be shot with Program, Aperture-priority, Shutter-priority or fully Manual exposure. Sound comes courtesy of a built-in, stereo microphone by default, or you can connect an off-camera microphone courtesy of a standard 3.5mm stereo mic port. There's also a 3.5mm stereo headphone port, which means that you can monitor audio levels before and during capture. And the K-1 provides levels display before and during capture, completely with a peak hold function, and separate display of left / right channels.

The K-1 also allows autofocus during movie capture. It's not the fastest and it only provides single operation, rather than full-time autofocus. Still, it means you don't have to pull focus manually or set your shoot up so as to keep your subject within depth of field.

There's still a 25-minute / 4GB clip length limit in the Pentax K-1, and so if you need to have longer continuous shooting, you'll need to look for another solution. Sadly, there's also no clean HDMI output, so recording externally isn't an option.

And we mentioned that the Pentax K-1 supports interval movie capture. This works much as it did in earlier flagships, and shoots at up to 4K resolution (3,840 x 2,160 pixels). If your clips are lengthy, you can expect some seriously colossal file sizes -- around 3GB per minute -- at this resolution, thanks to the Motion JPEG / AVI compression. That said, the ability to shoot ultra high-def time-lapse video is nevertheless pretty cool.

Wi-Fi wireless communication

Helpfully if you want to get your photos online or into your client's hands as quickly as possible, the Pentax K-1 includes in-camera Wi-Fi wireless networking connectivity. Through a free "Image Sync" app for both Android and iOS smartphones and tablets, the K-1 can be controlled remotely, complete with a live view feed and the ability to adjust variables such as shutter speed, aperture and ISO sensitivity. It's a much more integrated solution than in past Pentax flagships, which at best have offered compatibility with Eye-Fi cards for image transfer, or with Pentax-branded Flucards for image transfer and remote control.

Connectivity

In almost all respects, the Pentax K-1 is a significant upgrade over the crop-sensored K-3 and K-3 II. In one respect, though, it rather curiously trails both cameras. Where the earlier K-3 and K-3 II sported USB 3.0 SuperSpeed data connectivity, the K-1 reverts back to the far more common -- but rather slower -- USB 2.0 High Speed. If you prefer to swap your SD card to another devices instead of transferring data through a cable, then you'll not even notice the change. If you appreciated the higher transfer rates possible with the K-3 siblings, though, it might be time to invest in a fast card reader and change your habits.

Acknowledging that standard-def is now a thing of the past for most of us, the Pentax K-1 offers only a high-definition Type-D Micro HDMI output. We've already mentioned much of the K-1's remaining connectivity, which includes 3.5mm stereo mic and headset jacks, an intelligent hot shoe, cable switch terminal, PC sync terminal, front and rear infrared receivers, and a connector for the optionally-available D-BG6 portrait / battery grip. There's also an 8.3V DC input, which works with the K-AC132 AC adapter kit.

Storage

Storage is catered for with dual SD card slots. These are compatible with both the higher-capacity SDHC and SDXC cards, as well as the higher-speed UHS-I cards, the latter up to the maximum bus speed of 104MB/second.

Power

The Pentax K-1 retains the same D-LI90 battery as all of Pentax's other flagship models since the original K-7. The combination of battery and K-1 is rated as good for 760 shots on a charge, or 390 minutes of playback. That's just slightly better than the K-3 II in record mode, as that model was rated for 720 shots on a charge. Note that when comparing with other models, you'll need to account for the lack of a flash strobe in the K-1. (The standard CIPA test uses the flash for every other shot if the camera has one, increasing power consumption.)

Battery grip

Add on the optional D-BG6 portrait / battery grip, and you'll be able to put a second battery pack in the camera for double the battery life. (You'll also be able to use six standard AA batteries in the grip if you can't get to a charger, and a spare flash card can be stored in one of the two battery inserts that are supplied with it.)