Pentax K-3 Mark III Monochrome Review

Pentax’s K-3 Mark III Monochrome ($2,199.95, body only) is one of a few digital cameras that capture photos exclusively in black and white. It takes the classic SLR body style and sensor from the standard K-3 Mark III ($1,999.95) and simply omits the filter that creates colors. The camera doesn’t autofocus as well as mirrorless models, but other black-and-white competitors have more serious limitations; the lux Leica M11 Monochrom ($9,195) is manual focus only, for example, while the Q2 Monochrom ($5,995) uses a fixed lens. We’re still waiting for a dedicated black-and-white model with all of the advancements of mirrorless systems, but the K-3 Mark III Monochrome earns our Editors’ Choice award in the meantime thanks to its accessible price and fantastic photo quality.

Everything Looks Better in Black and White

The idea of a black-and-white digital camera isn’t exactly new, as Leica released its first M Monochrom rangefinder ($7,950) back in 2012. High-end medium format brand Phase One also sells an Achromatic back for its IQ4 system ($55,900 with camera body), though I don’t see it as a practical option for most people. Aftermarket conversions like MaxMax’s D780 Monochrome ($5,692.50) exist as well but are quite pricey. All of this is to say that the K-3 Mark III’s down-to-earth price is a welcome change.

(Credit: Jim Fisher)

You should know that there are real-world reasons to choose a camera that sees the world in only shades of gray, versus editing color photos to be black and white. Camera sensors are monochrome by design, with most models adding a Bayer color filter array (CFA) to filter out red, green, and blue wavelengths and turn shades of gray into color. Because a CFA cuts out different wavelengths of light at different photosites, not every pixel gets ample light when you snap a photo. Cameras use software to fill in those gaps, interpolating missing data based on the surrounding pixels.

The CFA also restricts how much light the sensor sees by about an f-stop, so black-and-white cameras have an inherent low-light advantage; color noise is nonexistent and luminance noise has a film grain quality. The tones of gray and transitions from light to dark are smoother and richer than with a converted color photo too, though I admit that’s not a quantifiable property.

(Credit: Jim Fisher)

On the downside, you’ll need to use color filters for your lenses if you want a creative effect. In black-and-white photography, different colored filters affect how dark or light a tone of gray appears in photos. For example, landscape photographers may opt for a red filter, since its position on the color wheel makes blue skies appear dark (clouds pop out more dramatically) and foliage tones look deeper. A yellow filter, my preference, achieves the same effect, but not as intensely. An orange filter goes in between the two. On the opposite end, blue and green filters lighten skies and foliage. With the K-3 III Monochrome, you have to use glass filters on lenses for color balancing. With a color camera and the right software, you can apply these filter effects digitally, either in a Raw processor like Lightroom Classic or a specialty app like Silver Efex Pro (part of the Nik Collection by DxO).

The need for glass filters isn’t the only old-school aspect of the K-3 III. After all, it’s an SLR with an optical viewfinder. To be fair, the Leica M11 Monochrom is a rangefinder, an even more niche type of camera that doesn’t support autofocus or video.

(Credit: Jim Fisher)

Aside from some color choices on the exterior, the K-3 Mark III Monochrome is the standard edition’s doppelgänger. It measures 4.1 by 5.3 by 2.9 inches (HWD), weighs 1.8 pounds, and feels sturdy. The chassis is magnesium alloy and includes Pentax’s well-regarded weather sealing. The brand has long been popular among outdoor photographers for good reason.

The K-3 Mark III works with Pentax’s lineup of K-mount lenses, which covers the basics. I used the camera with a broad selection, including some DA Limited primes, the 150-450mm telezoom, and some older manual primes. The camera also supports manual focus glass going back as far as 1975, as well as M42 thread mount lenses via an adapter in case you have a set of old Pentax Super-Takumar primes. The M11 Monochrom is a little more flexible in terms of lens support since it can take any SLR lens with an adapter. Of course, it is manual focus only and M-mount glass is a requirement for focus through the optical viewfinder.

(Credit: Jim Fisher)

As mentioned, the K-3 Mark III Monochrome is the same camera as the regular K-3 Mark III from a design perspective. Pentax does a few things differently with its control surfaces compared with more conservative alternatives like the Canon EOS 90D or Nikon D780, however. The K-3 III’s grip is worth mentioning, too. Its deeply indented middle finger rest feels quite comfortable and I like the slightly angled control dial.

(Credit: Jim Fisher)

The Pentax also includes a couple of extra dials on the top plate. One swaps between the optical viewfinder, the stills live view, and the video capture mode. A second surface called the E.Dial works along with the nearby S-Fn button to toggle through a few different functions. You can use it to set EV compensation, adjust the ISO, swap between a pair of in-camera crop options (1.3x and 1.7x), switch between a few preset focus settings, and toggle overlay grids for the optical viewfinder.

The top also includes a monochrome info LCD with a backlight, EV and ISO buttons, and an on/off switch that rings the shutter release. The Mode dial is at the far left with a clever, nestled lock system. When the lock is engaged, you can still turn the ring as long as you hold down the central push-in button at the top of the dial.

(Credit: Jim Fisher)

The left panel focus controls are not Pentax-exclusive but are as useful here as they are on a Nikon. The K-3 III has an AF/MF toggle and AF Mode button to set focus mode, along with an SR button to toggle the Shake Reduction stabilization system and a Raw button for on-demand Raw format snaps. I don’t find that last function useful since I leave cameras set to Raw mode all the time, but you can reassign both it and the SR button’s functions.

The rear is a little more standard. Lock and Delete buttons are at the top left corner, with Play and AF buttons flanking a rear control dial on the right. The camera also has an eight-way focus joystick, four function buttons that double as a d-pad, an Info button, and a Menu button. The Green button also appears, although it’s not actually painted green here, it has a gray finish that matches the camera’s monochrome style. Regardless of its actual color, the Green button is a Pentax innovation that resets exposure settings in Program mode or puts the camera in Auto ISO mode if you press it and the ISO button together.

(Credit: Jim Fisher)

Viewing the World Through a Tinted Viewfinder

The K-3 III Monochrome includes an optical, through-the-lens viewfinder for eye-level photography and supports live view on its fixed rear display. The optical viewfinder is a throwback in an era when most cameras use electronic viewfinders (EVF) but it’s the best you can find on an APS-C format SLR. Its large magnification (0.70x with a standard-angle lens focused to infinity) is at full-frame quality for SLRs and nearly as large to the eye as you get with upmarket mirrorless alternatives like the Fuji X-T5 (0.80x).

(Credit: Jim Fisher)

The viewfinder’s matte finish is a plus for manual focus—It helped me get in-focus shots with a vintage SMC-M 50mm F1.7, for instance. Still, the rear LCD does a better job for pixel-peeping precision. It supports different framing grid overlays, letting you pick between an unobstructed view, one with a focus area outline only, a Rule of Thirds grid, and a square grid.

SMC-M 50mm F1.7, f/1.7, 1/3,200-second, ISO 400 (Credit: Jim Fisher)

On the downside, I find the focus indicator points hard to see in dim conditions. I took the camera to a local railroad museum and lost the point of focus a few times when I tried to capture black locomotives. The focus points flash red when you move them and when the camera confirms focus, but the illumination period is too brief. You also must contend with a tinted view, at least if you opt to use a color filter. I didn’t have filters for all of the lenses I used with the camera but found myself looking through a yellow-veiled world when I did. That’s not something you need to think about with the M11 Monochrom; it’s a rangefinder, so its viewfinder doesn’t show a through-the-lens view. The Q2 Monochrom doesn’t have this issue either thanks to its EVF. Looking through a color filter is nothing new if you’re used to shooting black-and-white film with an old 35mm SLR, of course.

(Credit: Jim Fisher)

The K-3’s 3.2-inch rear display is sharp (1.62 million dots) and supports touch input, but doesn’t offer any articulation. I count that as a downside for this version of the K-3 III in particular, as I expect the monochrome nature to appeal to photographers who use manual focus lenses. A tilting screen simply makes tripod and manual focus work more comfortable. The M11 Monochrom’s rear display also has a fixed design, but you can purchase the tilting Visoflex 2 EVF ($740) to get live view articulation.

SMC FA 31mm Limited, f/1.8, 1/3,200-second, ISO 200, yellow filter (Credit: Jim Fisher)

Long Battery Life

The long-running D-LI90 battery powers the camera. Despite its age (Pentax launched it in 2009 with the K-7), it supports in-camera charging and has a healthy 800-shot CIPA rating, better than most EVF cameras. Pentax does not include an external charger to replenish the battery out-of-camera, but the K-3 III ships with a USB-C cable and an AC adapter.

SMC FA 31mm Limited, f/1.8, 1/60-second, ISO 5000, yellow filter (Credit: Jim Fisher)

Two SDXC card slots handle storage, though only Slot 1 supports UHS-II transfer speeds (up to 312MBps). Slot 2 tops out at the slower UHS-I rate (104MBps). In addition to a USB-C port, the camera includes 3.5mm microphone and headphone jacks, a micro HDMI connector for video, a 2.5mm remote control port, a PC sync socket for studio flashes, and a hot shoe for an on-camera strobe or wireless transmitter. The body does not include a flash.

The camera pairs with the Ricoh Image Sync app (available for Android and iOS) for wireless transfer and remote control. Bluetooth 4.2 and Wi-Fi 4 radios are on board to facilitate that connection. Those aren’t the latest specs but are still adequate. The pairing process to the app is a little convoluted, though not difficult: You need to type the camera’s Bluetooth identification into the app manually and then enter a code. The app lets you browse photos from the camera’s card and download them to your phone. Transfers are reasonably fast. I copied a DNG image from the camera to my iPhone in about 10 seconds and a JPG in about half that time.

HD D FA 150-450mm, 450mm, f/11, 1/500-second, ISO 1600 (Credit: Jim Fisher)

Night sky photographers might look to the K-3 III Monochrome as an alternative to specialized monochrome telescope cameras like the QHY600PH-M ($4,599). To that end, Pentax puts its Astrotracer function into the body. This lets you shift the sensor during long exposures to compensate for the rotation of the earth and cleverly works with or without the O-GPS2 add-on ($179.95).

Excellent Focus…for an SLR

There was a time when SLR cameras were class leaders in autofocus, but no longer. Mirrorless cameras focus more quickly and accurately than any optical viewfinder camera, as well as spread focus coverage to the edges of the sensor. Like other SLRs, the K-3 Mark III Monochrome restricts its autofocus coverage to a narrower area, visible in the diagram below. It’s among the broadest coverage areas for an APS-C SLR, lagging behind only the out-of-production Nikon D500, which puts focus closer to the edges of the frame. Although the K-3 III can focus across its entire frame in Live View mode, it uses a slower, contrast-based method when you switch to the rear display. The latter is thus more suitable for landscapes and photos of stationary subjects.

(Credit: Ricoh Imaging)

The focus system supports single (AF-S) or continuous (AF-C) focus, lets you select an individual focus point, cluster, or zone, and offers face detection for people through the viewfinder. It’s mostly effective in practice, though your lens choice can sometimes have an effect. Lenses with screw-driven focus, like the SMC FA 31mm Limited, focus quickly, though audibly. Newer lenses with internal focus motors are quieter, though some like the HD DA 20-40mm F2.8-4.0 Limited are on the slow side and cut down the hit rate for candids and action shots.

HD D FA 150-450mm, 450mm, f/5.6, 1/500-second, ISO 800 (Credit: Jim Fisher)

I tried the camera with the HD D FA 150-450mm to see how the focus system handles wildlife and other uncooperative subjects. The lens kept up with the Monochrome’s focus system, but the camera puts more onus on the photographer to get the focus point right on the eye of an animal, which led to plenty of shots that were just out of focus. Many mirrorless cameras are smart enough to move focus to an animal’s eye when the focus box is on the body. Compared with other monochrome cameras, however, the K-3 III leads the pack in autofocus performance. The Leica Q2 Monochrom has a wider spread and eye detection for people, but its fixed 28mm F1.7 lens is unsuitable for wildlife and field sports. And, again, the M11 Monochrom is manual focus only.

HD D FA 150-450mm, 450mm, f/5.6, 1/500-second, ISO 800 (Credit: Jim Fisher)

The Pentax claims a maximum drive speed of 12fps, but I couldn’t get past 11fps in testing. The buffer holds about 88 JPGs or 40 Raw pictures. A full burst of photos clears out to a 299MBps Sony Tough UHS-II SDXC card in about 10 to 15 seconds. If you’re eyeing the camera for unique sports or wildlife photos, it’s fast enough for either task. Just make sure to choose a fast-focusing lens, such as the HD FA* 70-200mm F2.8 ($1,799.95) and HD DA 55-300mm ($449.95). I haven’t tested either but system photographers regard each highly.

HD D FA 150-450mm, 450mm, f/5.6, 1/500-second, ISO 1600 (Credit: Jim Fisher)

Black and White, With Stabilization

The K-3 Mark III Monochrome puts its 25.6MP sensor on a 5-axis stabilization system, an uncommon feature among SLRs. The imager is a BSI CMOS chip without a CFA and covers a broad ISO range (200-1600000). The camera snaps 14-bit Raw pictures in either the Pentax PEF or Adobe DNG container format, as well as captures 8-bit JPGs.

HD DA 40mm Limited, f/2.8, 1/400-second, ISO 200 (Credit: Jim Fisher)

It’s possible to get pleasing JPGs out of the camera, but this camera practically requires you to turn on Raw capture and dedicate time to post-processing. Almost all color cameras, including the standard K-3 Mark III, have black-and-white JPG modes as options for photographers who prefer not to edit.

If you decide to use the K-3 III Monochrome for JPGs, you have some flexibility in how they look. The camera has three processing modes for standard, soft, or hard tones, each with an adjustable highlight, contrast, and shadow response. The blue, sepia, and selenium profiles available for Leica Monochrom cameras are missing from the Pentax, however, so you’ll have to make do with just basic black and white.

HD DA 20-40mm Limited, 20mm, f/8, 1/50-second, ISO 12800 (Credit: Jim Fisher)

Just because the ISO goes up to 1.6 million doesn’t mean that pictures look good at those settings. In practice, the K-3 III Mono is usable for typical photographic applications up through ISO 204800, still a fantastic figure for low-light imaging. Photos from my ISO test scene show superb detail and very little grain at lower ISOs and practically no noise through ISO 1600. Pictures in the ISO 3200-6400 range reveal a fine grain pattern but don’t lose much resolution. Noise starts to roughen and cut away some contrast in the ISO 12800-51200 range, with rougher results (think high-speed films of yore like Kodak TMax P3200 and Ilford Delta 3200) at ISO 102400-204800. Picture quality falls apart starting at ISO 409600.

HD D FA 150-450mm, 450mm, f/5.6, 1/500-second, ISO 400 (Credit: Jim Fisher)

At lower ISOs, the K-3 Monochrome affords you a wide latitude for editing exposure. There’s seemingly unlimited room to open up details in the shadows. Moreover, the sensor does such a good job controlling noise that you don’t have to worry about pushing exposure, assuming you start with a reasonable ISO.

HD D FA 150-450mm, 450mm, f/5.6, 1/800-second, ISO 200 (Credit: Jim Fisher)

The sensor has fewer pixels than the 60MP chip for the Leica M11 Monochrom, but the latter camera lacks the in-body stabilization of the K-3 III Monochrome. The system is good for 5.5 stops of correction and works regardless of the lens you attach. I managed consistently sharp handheld photos at 1/4-second with the DA 20-40mm and extended to 1/2-second with hit-or-miss results. The only downside to Pentax’s decision to use IBIS is that the company relies on it exclusively, completely eschewing in-lens stabilization across its K-mount catalog. With wide-angle lenses like the 20-40mm, that’s not a problem. But you’ll contend with a shaky viewfinder and less effective stabilization when you use telephotos like the HD D FA 150-450mm handheld or focus close-up for macro photos with the HD D FA 100mm F2.8.

HD DA 20-40mm Limited, 20mm, f/2.8, 1/50-second, ISO 500 (Credit: Jim Fisher)

As mentioned, the positives of a monochrome camera over color models include superior resolving power, better dynamic range, and less obtrusive luminance noise. The improved resolution stems from the camera’s ability to record light at every pixel site, without the interpolation that comes with a Bayer CFA sensor. The wide dynamic range and extra-crisp detail work together to give photos richer tones of gray than you get with black-and-white images edited from color sensors, a subtle yet important differentiator.

HD DA 20-40mm Limited, 28mm, f/5.6, 1/250-second, ISO 200 (Credit: Jim Fisher)

On the downside, you need to use glass color filters to balance tones of gray, and there’s no way to recover a highlight that’s lost to overexposure. Due to the latter, you should switch from the default Multi-pattern metering setting to the Highlight-weighted option that looks for the brightest parts of a scene and sets the exposure to avoid clipping. You might end up with underexposed photos at times (fixable in post), but you won’t risk irrevocable overexposure.

4K Video, With a Crop

The K-3 Mark III supports 4K at 24 or 30fps and adds a 60fps option if you drop down to 1080p, saving 8-bit H.264 video in QuickTime MOV format. The same standard, hard, and soft tones for JPGs are options for video, with the soft look providing a low-contrast picture that serves as a good starting point for color correction (or more accurately, contrast correction). The camera also has three digital filters for video: Retro puts contrast somewhere between the soft and standard looks, High Contrast draws scenes harshly, and Invert Color records with a photonegative effect.

HD DA 20-40mm Limited, 20mm, f/8, 1/60-second, ISO 400 (Credit: Jim Fisher)

Video quality is fine overall, just not as impressive as for stills. For example, the 4K mode introduces a 1.5x crop, so wide-angle lenses don’t provide as broad a view in stills mode. I see some Jell-O motion with handheld video too, and the H.264 compression lags far behind newer formats for editing exposure. Continuous autofocus isn’t available either, so you need to drive it manually if you want to rack focus during a shot.

HD D FA 150-450mm, 450mm, f/5.6, 1/500-second, ISO 1000 (Credit: Jim Fisher)

It may be fun to use the K-3 Monochrome to channel your inner Ingmar Bergman and make monochrome movies. But if making films requires a camera with ProRes encoding and uncropped 4K works better as a starting point, the Fuji X-H2S is far better. Its Acros profile is fantastic for black-and-white takes in-camera and the camera offers a flat color profile with ProRes 422 for advanced editors who want to create monochrome grades.

SMC FA 31mm Limited, f/22, 1/1,600-second, ISO 400, yellow filter (Credit: Jim Fisher)

A Real Photographer’s Camera

If you love making black-and-white pictures, there’s nothing quite like using a camera made for that sole purpose. Up until now, photographers in this camp had to pay exorbitant prices for a Leica M rangefinder or a converted aftermarket model, but the K-3 Mark III Monochrome makes the experience far more accessible. It’s reasonably affordable, offers familiar SLR ergonomics, and includes modern conveniences such as autofocus and image stabilization. And most importantly, it produces superb images. The K-3 Mark III Monochrome ultimately lacks the cachet and full-frame sensor of the M11 Monochrom, but its practicality and reliable performance earn it our Editors’ Choice award for black-and-white sensor cameras.

Thanks to B&H Photo for providing a K-3 Mark III Monochrome for review.