Pentax 645Z Field Test Part I

Ricoh's mighty medium-format takes on the mile-high city

By Mike Tomkins | Posted: 09/10/2014

The Pentax 645Z arrived just in time for an already-planned trip to Denver, Colorado. And boy, was I ever thrilled to have it along for the ride!

I've shot with many professional DSLRs over the years, right back to when even the most expensive of pro gear consisted of digital innards shoe-horned into a repurposed film SLR body, but there was one type of camera that I'd never managed to get my hands on -- at least, away from the trade show floor. Until now, I've never had the chance to shoot a medium format DSLR. The Pentax 645Z is a first for me, and it's one I've been greatly anticipating. I don't think it's too much of a spoiler to say that it's living up to my expectations.

As I said on our news page when I posted my Pentax 645Z gallery a few days ago, this could never be considered a stealth camera. For a medium-format camera, it's actually reasonably compact, with similar width to a professional full-frame DSLR like the Canon 1D X or Nikon D3/D4-series, and since it lacks a portrait grip, it's significantly less tall than any of these. But with the best will in the world, there was little Ricoh could do to reduce its depth -- it has to fit in a medium-format mirror box, after all -- and so it's in this dimension that the Pentax 645Z stands out from other pro cameras. Depending on which of these pro cameras you choose to compare it to, the 645Z is about 30-50% deeper.

That makes it look much bulkier, although truth be told the difference really isn't that great. The 645Z's weight is almost indistinguishable from that of the Canon 1D X, despite its much larger sensor, and if you simplify and compare the outer bounds of each camera's dimensions, the Pentax is only about 5% larger than Canon's pro camera. And if you make a fairer comparison to something with similar sensor size and resolution -- say, a Phase One IQ250 digital back on a 645DF+ camera body, say, or Hasselblad's H5D-50c -- the Pentax 645Z is both quite a bit smaller and weighs significantly less as well.

My first few days in Colorado were, sadly, rather rainy and dreary -- but that gave me a chance to familiarize myself with the camera, and let me test out the weather-sealing. Lemonade out of lemons, folks!

But that squat, square profile draws attention, because it looks noticeably different to anything else most people will ever get the chance to see. Folks who would probably never show an interest in most camera gear spot that difference, and if they're even slightly interested in photography, they come up and talk to you about the camera. And that's with relatively compact lenses mounted, as well -- I can't begin to imagine how much attention you'd draw with, say, a 300mm or 400mm prime mounted.

After that first few days, the sun broke through, and the weather got progressively nicer for the rest of the trip.

Once I slotted a battery into the 645Z, I was in for a surprise. I was expecting, given that its larger sensor also means a larger mirror and viewfinder, that it would be quite a bit louder than an APS-C or full-frame DSLR, but it's not, really. In fact, I'd say some consumer DSLRs I've shot with have actually been louder! Again, it's not stealth -- the 645Z is certainly not a camera you'll sneak up with and take photos without anybody realizing -- but it's certainly not unduly loud either.

Now that 645 optics from the film days are back in production and available in the US market, there's a fair selection of glass available for 645 mount. Sure, it's predominantly older designs that predate Ricoh's 645 digital SLRs, but it works just fine with digital too. At the current time, you can choose from 17 optics -- of which three are DA or D FA digital-specific designs, and 14 are FA designs originally intended for film use.

Between them, you can cover everything from a 25mm wide angle to a 400mm telephoto. Not surprisingly for a camera format aimed at those seeking ultimate resolution and image quality, they're predominantly high-quality primes, although there are a few zooms to choose from as well. (And between the zooms, you can manage everything from a 33mm wide angle to a 300mm telephoto without any gaps in coverage.)

Along with the camera, I received an smc PENTAX-D FA645 55mmF2.8 AL[IF] SDM AW prime lens for test, a nice pairing that matched the all-weather design of the camera body with an array of seals in the lens as well. With a trip to Colorado looming, and no time for Ricoh to source further lenses for me, I checked in with our good friends at LensRentals. They have a fairly healthy selection of 645 lenses available, and while a good number of them were already rented, two were ready to be shipped to me in time for the trip: the smc PENTAX-FA645 75mmF2.8 and smc PENTAX-FA645 MACRO 120mmF4.

Photos shot with the 645Z are absolutely packed with razor-sharp detail. I'll talk more about high sensitivity / low-light shooting in my next Field Test, but at lower sensitivities, noise is pleasantly film-like.

Although that left me with nothing wider than a 44mm-equivalent, perhaps not ideal for Colorado's sweeping mountain vistas, I was happy I'd be able to make do nevertheless. And of course, I brought along a tripod, too. My Feisol Traveler CT-3441S is rated as good for up to 22 pounds, far more than sufficient for the heaviest pairing I'd be shooting with, the 645Z with 120mm f/4 lens. (Together, these weigh just five pounds -- hefty for someone used to shooting a consumer or enthusiast DSLR, but not unreasonable compared to other pro cameras.)

At default settings, color is much as I expect from my APS-C Pentax DSLR: for the most part quite accurate, but with gently boosted saturation. Of course, you can tweak it to your tastes.

This was my first trip to Denver, originally planned to visit some close friends who'd moved out of state earlier in the year, so I didn't have too much idea where the best photo opportunities lay. A little while spent on Google, TripAdvisor, and a variety of other sites turned up some promising locations, though, and for a first visit I think I managed pretty well. (Both on the photo front, and getting to see some cool sights with my family and friends.)

Unfortunately, the first few days' weather weren't terribly cooperative, with lots of sudden, heavy rain showers and ever-present storm clouds. While I still got out and shot with the 55mm f/2.8, greatly appreciating the weather-sealed nature of body and lens, dreary skies meant relatively few shots like those I was looking for. Still, it gave me a great chance to familiarize myself with the camera, which had landed on my desk right before the trip when I was in full-on panic mode, trying to finish everything that had to be done before I left the office. And it gave me the chance to test that weather-sealing, too, which handled the rain with aplomb. (I expected no less, as I've shot with my APS-C Pentax DSLRs in the rain many times, and never experienced even the slightest concern.)

While I'm pretty familiar with Pentax's user interface and ergonomics as a long-time Pentax DSLR shooter, I was glad of that familiarization time. A fair few controls are shared with the company's APS-C DSLRs, but several do differ significantly -- especially the focus*, bracketing, and still / movie controls. And of course, there are some differences in the menu system, too.

Autofocus is swift and accurate when shooting through the viewfinder. In live view mode, it also works quite well, but the dedicated phase-detection sensor handles low light better. One quirk: the AF points are clustered near the center of the frame. I often found myself having to reframe images even when using the outermost AF points.

* (One difference in the focus controls applies only if you're not already shooting the Pentax K-3. The 645Z incorporates the new focus area selection button introduced on that camera. My own K-5 lacks that feature, so I had to teach myself to remember that control all over again, just as I did when I reviewed the K-3. And for those of you who read my Pentax K-3 review where I said I'd be buying one, yes, it's still on my shopping list. I've told myself I have to sell some camera gear I don't use any more before I'm allowed to buy it, though.)

This isn't a camera I'd want to use for shooting sports or particularly active subjects, but it did fine at keeping up with my hyperactive five-year old..

For the most part, I found myself liking the 645Z's control layout right off the bat. I'd like to see some differentiation in feel for the row of buttons that line the left shoulder of the mirror box, however. All four are the same size and shape, and that makes it harder to remember which is which, with the viewfinder raised to your eye. The viewfinder, though, is gorgeous. It's large, bright, and very clear, making it pretty easy to focus manually. And the huge, soft, screw-off rubber eyecup shields extraneous light pretty well.

The tilting LCD monitor beneath does project quite a way from the camera's rear deck, and presses a bit uncomfortably on the side of my nose when framing with the viewfinder, but I'm happy to put up with that for the versatility it adds. I found myself switching to live view mode and shooting with the LCD tilted up or down quite a bit, and it's quite refreshing to see a manufacturer that's not afraid to put an articulated display like this on a weather-sealed, pro-oriented camera.

Overall, the 645Z feels well laid out, and quite a comfortable transition if you're already used to shooting with one of Pentax's enthusiast DSLRs from the last few years.

Once the run of troubled weather finally broke a few days into my trip, I got out and shot with the 645Z every single day, taking it everywhere I went with my wife serving double-duty as patient mother and lens caddy. (Thanks, Bethany!) And boy did I ever have fun. Other than the weight being a bit greater than I'm used to, the burst performance understandably rather slower, and the autofocus point coverage quite tightly clustered around the center of the frame, the 645Z shoots much as you'd expect of a pro-grade camera.

Having a large medium-format sensor helps out when you want to isolate subjects from their background with depth-of-field blur. You do have to watch out that you've actually managed to fit your whole subject within what can sometimes prove to be a razor-thin sweet spot of focus, though!

It focuses swiftly and confidently, and it provides a generous burst depth that ensured I never felt I was left waiting for the camera. Most of the time, I was shooting three-frame raw+JPEG bracketed exposures, as I tend to do for reviews. While I'd certainly have appreciated faster burst shooting, this isn't really a camera I'd choose for sports, and the 3-fps burst capture rate at full resolution felt quite sufficient. I did find myself wishing for a quicker image review occasionally, though -- it can take quite a few seconds for images to appear onscreen after a short burst -- but if you can live without bracketing every shot as I did for insurance, that's not as much of an issue.

Although your telephoto options are somewhat limited by the larger-than-35mm sensor, currently-available Pentax lenses will take you out to 320mm-equivalent without converter. Here, I was shooting with the smc PENTAX-FA645 MACRO 120mmF4, which is effectively a 96mm optic when used on the Pentax 645Z.

And given the file sizes we're talking about here, those slight performance concerns are really very understandable. In fact, the file sizes were enough that my laptop -- a mid-range Sony VAIO from a couple of years ago chosen mostly for its very bright, outdoor-visible screen that lets me work outdoors -- actually struggled to deal with browsing large quantities of images. Here, I found the 645Z's dual card slots a great boon, as I simply shot JPEG to one card and raw to the other, never touching the raw card until I'd finished my image browsing and selection from the easier-to-handle JPEGs. If you're going to shoot raw and do much work in the field, though, I highly recommend a higher-end laptop to pair with this high-performing camera. (And if you're spending US$8,500 on a camera body, you can doubtless justify the expense of a suitable editing companion.)

Once I got those images onto a larger screen and looked at them... wow. This camera can capture a truly staggering amount of detail, and it does so with the Pentax look I know and, honestly, very much like. Although we've consistently commented on Pentax's handling of the red fabric swatch in our Still Life test scene, where it loses detail compared to some rivals, it's worth noting that we're using default color rendering in this test. I've never found it a significant issue in the real world, and even if it is -- well, there's a great range of control available to tweak the rendering to your own personal tastes.

I did find the default program line tends just slightly slower than I'm comfortable with in terms of shutter speed, though, just as it does with my K-5. That's easily fixed by either switching to the Sports program line or paying attention to shutter speed when shooting. (I did the latter, predominantly shooting in MTF mode and bumping ISO sensitivity to get a shutter speed I was comfortable handholding. When I didn't pay close-enough attention I sometimes got ever so slightly soft results when viewed 1:1, although they'd still be plenty good enough for printing.)

I found myself wishing for a more telephoto lens when we drove out to Steamboat Springs. The reason: A black bear which appears only ~100 pixels tall (or 1.2% of the image height) in this shot of the Routt National Forest. I'd have loved to have gotten closer, but perhaps understandably, not on foot!

Exposure metering was pretty consistent, with just a touch of negative exposure compensation needed to hold onto the highlights in JPEG mode. I don't see the need to tweak exposure consistently as a problem, to be honest -- it's when a camera's metering is all over the place that I'd have a complaint. Here, I'd just dial in a 1/3-stop of negative exposure compensation, and call it a day. (Well, truth be told, I'd shoot in raw mode, but I like to have a lot of control over my photos.)

Yes, the sky really was this blue. I had a hard time believing it myself! Perhaps it's the altitude?

And towards the end of the trip, we finally got some blue skies which I can only describe as startling. You may be tempted to question them, but don't. I'm not sure if it's a function of altitude -- we were in Steamboat Springs at close to 7,000 feet once the weather finally changed for the better -- but I'd say those deep blues actually reflect what I saw in person pretty darned well.

I've never seen skies quite this blue before -- it was truly spectacular. (And although we didn't have any other cameras with us for a side-by-side comparison, shots from our Apple and Sony smartphones that we shared on Facebook that day have much the same color, albeit with far, far lower resolution.)

And as we'll see in my next Field Test, coming soon, the 645Z's high resolution and pleasing images are coupled with what, by medium-format camera standards especially, is an absolutely epic ISO sensitivity range. That, coupled with the weather-sealing and movie capabilities really take this camera into a class of its own, as far as I'm concerned.

But I'll have more on all of that in the next Field Test, coming soon... watch this space!