Phase One XF 100MP Field Test Part I

Phase One XF 100MP Field Test

A test-drive with the highest-resolution camera we've ever used

by William Brawley | Posted 10/03/2016

The Phase One XF 100MP: A camera on another level

I've had the opportunity to test and use a number of different kinds of cameras, from pocketable point-and-shoots to big, full-size DSLRs. For me, while I've known about medium format cameras for a long time, they were always sort of "out there;" a camera system that for the most part was way too expensive for a mere mortal such as myself to ever own, let alone even have the need to rent one. So, when Phase One came knocking at IR's proverbial door asking us if we wanted to test their new XF camera system with a 100-megapixel digital back, well, color me intrigued.

Getting the Phase One XF System is much different than just ordering from Amazon!

Right off the bat, the experience with this camera system was different than any other camera I, and most of the IR staff, have used. For starters, just acquiring the camera was out of the ordinary. Phase One won't just ship you a camera and some lenses. I mean, the base MSRP for this Phase One XF100 Kit rings up at just under $50,000! No, you need to get in touch with a Phase One partner retailer and have them hand-deliver the system to you. In our case, we coordinated with Capture Integration here in Atlanta for a hands-on demonstration session with the camera at their shop before we were set free with the gear.

The Capture Integration product tour of the Phase One system, as it turns out, was very helpful, as there are tons of minor tips and tricks as well as extensive tether-based shooting features that we do not typically see or use on "run-of-the-mill" interchangeable lens cameras. Sure, you could slap a lens on there, slide in a CF card, and fire away, but tethered shooting opens up a lot of expanded versatility.

The Phase One XF is a beast: big, bulky and a little awkward

Before we start discussing image quality or performance, let's talk about ergonomics: This camera is huge! That should be expected, given that the system is centered around a full-frame Medium Format sensor that measures 53.7mm x 40.4mm. I knew the camera was big, but still I wasn't expecting it to be as heavy and bulky as it was. Kitted-up, with camera body, digital back, viewfinder, the 80mm f/2.8 kit lens, and two batteries (one for the camera and one for the back), the camera weighs in just shy of six pounds! That's heavier than a Canon 300mm f/2.8L II lens.

Despite the size and weight, the grip is very comfortable

Apart from the weight, as you can see from the photos, the camera is quite boxy, and when used handheld, the bulk of the camera rests a lot into the palm of your left hand. The grip, on the other hand -- no pun intended -- is quite deep and contoured. And even though the overall camera system is large, the handgrip area feels more or less like a standard full-size DSLR. The camera fits comfortably into my hand, and the three control dials on the front and rear of the camera are easily operated by my thumb and forefinger.

Lots of touchscreen interaction

Interestingly, despite its large form-factor, the Phase One XF system relies a lot on touch-based interface, both on the top-panel LCD -- aka "the XF Grip LCD" -- and the digital back's large 3.2-inch LCD screen. While it does have an array of albeit unlabeled buttons that can be used for menu navigation or on-the-fly settings and exposure adjustments, much of the camera's settings can also be adjusted purely by touchscreen.

The digital back's menu system and user interface are fairly straightforward and easy to navigate for the most part. However, there were times when I had trouble remembering where certain settings were located within the array of menu categories. For one, the digital back has menu categories for both the XF camera body as well as the digital back itself; there's not a single "camera" menu, so to speak, as in other cameras. That being said, I would probably just chalk this up to my unfamiliarity with the Phase One system and that given enough time with the camera, that the menu navigation would become second nature. Thankfully, like an iPhone, if you get lost you can always "back out" to the main screen on the Phase One back simply by pressing and holding the top-left button on the back.

The touch-sensitive XF Grip LCD screen has its own menu navigation "language," which I found a bit more frustrating to deal with. On the one hand, the Grip LCD's top-level UI is quite handy, and you can simply swipe left or right between difference panes for either the main settings screen or various specialized shooting modes like timelapse, HDR or Focus Stacking, as well as composition tools like a simulated bubble level and a built-in seismograph (!) to monitor camera vibrations. The main camera settings screen (see on the right) on this top LCD is clear and easy to understand, and you can easily tap an icon to change its mode or view related options.

The Phase One XF is the first camera I can recall that has three separate control dials, and each control is set (by default) to adjust the three major exposure settings -- front dial for shutter speed, "side dial" (the one on the thumbrest hump) for aperture, and the rear dial for ISO. Pretty handy. Most cameras don't have such a setup, so I found myself tapping on the ISO icon on the LCD to make an adjustment before realizing all I needed to do was rotate its assigned dial.

For better or worse, all of the buttons and dials on the camera are unlabeled -- even the power button. For those just picking up this camera system for the first time, it can be a bit confusing as to which functions are controlled by any one button or dial. On the other hand, everything is customizable, so you can easily assign the functions that you need for your particular shooting style to any of the controls without any sense of confusion.

The primary confusing part of the Grip LCD's menu system was navigating *into* the menus. Using a combination of the two silver buttons as well as the three controls dials for selecting menus and moving into the menu hierarchy or back out again, it took a bit a fumbling around to get the hang of which buttons do what or which direction I needed to rotate a dial in order to navigate properly.

The rear LCD on the IQ3 100MP digital back, on the other hand, felt much more straightforward to use. The four silver buttons at the corners, depending on the menu screen at the time, would correspond to certain menus or functions. But, you don't have to use the physical buttons if you don't want to. Everything can be selected or navigated via touch, which is very nice.

The two touchscreens are fairly responsive, but I found at times that I needed to be pretty accurate with my tapping in order for my touch to register on the appropriate icon or menu item, or be recognized at all. Also, when shooting out in bright sunlight, I found both screens showed quite a bit of glare and could be difficult to read. Thankfully, to get around the glare -- at least when it comes to shooting and composing shots -- the Phase One system does include a traditional optical viewfinder.

Handheld shooting is certainly an option on the XF 100MP, but...

Despite its heftiness and bulk, the Phase One camera system can certainly be used handheld. The size certainly makes it more challenging to use if you're on the move in any way, and it's far from a stealthy rig. While the Phase One certainly feels more appropriate mounted on a tripod -- either in the field on in a studio -- there are a couple important things to keep in mind if you ever find yourself with one of these cameras and want to shoot handheld: focus and your shutter speed.

High resolution sensor makes focus and shutter speed all the more critical

Similar to my experience with the 50MP Canon 5DS R, the extreme resolution of the Phase One camera requires even more precise care when it comes to focusing and stabilization. Having your focus just a bit off is extremely noticeable when you magnify in at 100%. With such a large sensor and the potential for a super-shallow depth-of-field, it could mean the different in an eyebrow being in focus rather than the surface of the eye itself.

Furthermore, just like how the "1/focal length" shutter speed rule-of-thumb -- a.k.a. the Reciprocal Rule -- didn't really apply for the Canon 5DS R, the same can be said for the Phase One. Whereas I might have needed around 1/(2x focal length) for the 5DS R, the Phase One requires even faster shutter speeds -- maybe 1/4x. The 100MP resolution is so great that the risk of blurring at the pixel level is even more critical. For the most critically sharp images, and without resorting to raising the ISO, I'd recommend using a tripod for the Phase One whenever possible. Heck, the camera even has a built-in seismograph to help monitor camera vibrations and can even delay capture automatically if it detects vibrations above a set threshold.

...tethered shooting with Capture One is very powerful

Handheld shooting, in general, is certainly more flexible and convenient in my opinion, but the Phase One camera is much more appropriate on a tripod. You can get sharper photos, shoot longer exposures as well as take advantage of the camera's advanced shooting modes such as Focus Stacking and Timelapse.

The other main shooting scenario is studio-based with tethered capture into a computer. Bundled with a free* full version of Capture One, the tethering solution with the Phase One is amazingly robust and powerful. In fact, if you don't need to move the camera, as with product photography for instance, you could set the camera up and control pretty much the entire camera via the Capture One software on the computer. (*Capture One Pro is free for Phase One owners. Using the free Capture One "DB" mode is fully functional, but only works for Phase One raw files.)

For our standard lab shooting, the tethering capabilities were a big help. We need to get exposure, as well as framing and focus, to pretty precise tolerances, and the tethering setup really sped up our workflow once we got the hang of it all. One of the biggest time-savers with the tethered workflow was capturing a photo and then being able to immediately check the exposure levels, as well as make necessary exposure adjustments on the camera right away from the computer remotely. It was much simpler than our traditional workflow with a back-and-forth system of taking a shot, removing the memory card, checking the image on the computer, returning the card to the camera and repeating.

Furthermore, the large rear LCD was great for framing as well as focusing manually as it was both sufficiently large and sharp enough to ensure crisp focus. But, in cases where we weren't exactly sure, we could simply stream a real-time Live View signal out via USB (or HDMI) into Capture One and have a larger real-time view of the scene, which was pretty nice.

Phase One XF 100MP image quality is simply stunning

Of course, the big question regarding this 100-megapixel medium format system is its image quality. Simply put: Holy moly, this camera can capture some insanely detailed photographs! I could pretty much just stop there. The images are incredible.

Similar to our experience with the Pentax 645D and 645Z, the Phase One XF100MP's resolving power reveals textures and other fine details that are barely perceptible to the naked eye, especially when it comes to our Still Life test images!

Amazing detail that will certainly entertain the pixel-peepers!

The amount of detail that the Phase One XF100 can capture is stunning. It's quite a fun pastime now to zoom-in all the way (even past 100%) in Capture One and find yourself amazed that you can make out the brickwork detail of a far-off building or still read the license plate on what amounts to a speck-sized car when zoomed all the way out. It's incredible. Of course, most people do not need this much resolution in a typical photograph. However, for the target customer of this type of camera -- the fine art photographer, the landscape photographer, the editorial and advertising photographer -- the Phase One offers a staggering amount of resolving power, allowing for precise editing and retouching down to the finest detail.

Excellent dynamic range with tons of adjustability in post-production

Sheer resolving power aside, the Phase One XF100 captures images with fantastic dynamic range.  Using Capture One, I was able to recover tons of detail in the highlights, if I found myself with blown-out, overexposed areas. On the other end, I was also able to lift up the shadows to reveal lots of detail without introducing much noticeable noise.

Impressive high ISO capabilities offers a big step up from earlier CCD medium format cameras

And speaking of noise, the XF100's higher ISO capabilities are also quite impressive. Using a CMOS sensor compared to a CCD that a lot of earlier medium format cameras used, the Phase One XF100 has a maximum high ISO of 12,800. By comparison, a CCD-based Phase One back, such as the 80-megapixel IQ3 back, has a native high ISO of just 800.

The higher ISO image quality from the XF100 is excellent, given its sensor size and resolution. Personally, I'd have no issue shooting at ISO 3200 or 6400 with this camera. The images are impressively clean of distracting noise artifacts and still possess tons and tons of fine detail, even on tricky lower contrast areas like hair. When zooming to 100% on the RAW files in Capture One, you can, of course, see some fine-grained noise -- even ISO 12,800 doesn't look bad by any means, though I can see some slight false color banding. At higher ISOs, you do lose some detail compared to base or lower ISO images, but that's to be expected, medium format or not. All in all, while I wouldn't pick the XF100 as my go-to low-light/high-ISO camera, it's very capable and much more versatile in this regard, which wasn't typically the case for cameras in this category in years past.

The Phase One is far from speedy, but has a deep buffer for 100MP files

As for straight-up performance, the Phase One XF100 is not a speedy camera. Capturing 100MP shots, the Phase One is clearly all about capturing amazing detail and not about fast-action -- I certainly wouldn't make this my first choice for a camera out on the sidelines! If you do want or need to do a somewhat quick flurry of frames, the Phase One XF does have a continuous capture mode, but the burst rate is well under a frame per second. In fact, in our lab tests, we could fire off shots in single-shot mode at about the same rate as the continuous capture mode, regardless of the shutter mode (leaf shutter, focal-plane shutter or electronic first curtain shutter). Still though, we tested the XF100's buffer depth at over 60 frames with a fast Lexar Professional 1066x CompactFlash card. The burst rate may not be anything close to quick, but if you do find yourself needing to take a lot of high resolution images in a continuous scenario, the Phase One XF100 is capable at least when it comes to buffer depth.

Also, despite having a unique hybrid phase-detect and contrast-detect autofocus system, we found the XF100 wasn't a top-notch performer in terms of autofocus -- especially compared to traditional DSLRs. In good lighting and on high contrast subjects, as well as with smaller focus adjustments between shorter distances, the AF speed was fairly snappy. I did find that in low-contrast scenes, the AF performance could suffer somewhat, however.

See our Performance test results for details.

Despite its professional nature, the XF 100MP has its share of quirks

Now, while the image quality of the Phase One is stunning, it's not all smooth sailing when it comes to performance and usability. The Phase One system is complex, with both a camera body and digital back working in conjunction to form the camera. Then, add in a computer for tethering, and you're bound to run into a few hiccups.

Exposure problems had us dialing back the compensation dial

One of the first issues we noticed was a tendency for the camera to overexpose, both in the field and in the lab. Despite using the camera's default matrix metering mode and no exposure compensation applied, I often found myself with washed out, overexposed skies. For our lab shots, we were consistently having to manually underexpose shots slightly in order to match our stringent exposure levels for our test scenes. At default exposure compensation, shots were well outside of our exposure tolerance levels. Out in the field, I found myself having to consistently dial back exposure compensation by at least -0.3EVs, sometimes -0.7EVs. Thankfully, this isn't too much of an issue, as the Phase One files have excellent dynamic range. Be careful not to overexpose too much, however, and you'll have plenty of latitude in Capture One to pull back the highlights to reveal lost detail.

Freezing and odd exposure issues after the camera auto-sleeps

We also ran into issues with sporadic freezing and periods of unresponsiveness, particularly while tethered to Capture One. While photographing, the camera will give you a little "beep" to indicate the buffer is cleared and the camera is ready to fire the next shot. Now, while tethered, you can remotely trigger the shutter release and automatically send the captured image back to your computer. Sporadically, the camera would lockup and become unresponsive after a single shot. The camera would not respond to the Capture One software, either to fire off the next shot or adjust any exposure settings. The only solution was to turn the camera off and on again.

When asked about this behavior, our Capture Integration contact said that this issue could happen on occasion, for a variety of reasons such as the camera's power level or the computer's USB port power. Our assumption was that perhaps we were a little too "trigger-happy" and tried to fire off another photo before the camera had given off its "ready" beep after the previous capture. In any case, simply powering the camera off and on again cleared up any issue, and we were back in action once again. 

Another odd behavior we experienced in the lab was the camera's inability to respond to changing lighting conditions after auto-powering off from inactivity. In other words, after taking a series of shots in the lab, we'd leave the camera setup alone, but go off to review the images or go to adjust the lighting setup. In any case, there was a period of inactivity and the camera, by default, would go into a sleep mode to conserve power. However, upon waking up the camera, the auto-exposure settings, such as adjusting the shutter speed automatically in aperture priority mode, would not reflect changes in the lighting condition, thus resulting in an incorrect exposure upon taking the next photo. We could adjust exposure compensation once more to "fix" the exposure settings for the new lighting, or we could simply turn the camera off and on again.

Intermittent communication issues between body, lens and digital back

Our last strange hiccup with the camera seemed related to component communication, either between the lens and camera body or the body and the digital back. In one case, we had trouble with autofocusing. The various lenses we had all offered both AF and MF modes, with a sliding clutch or click-ring to toggle between AF and MF modes. Sometimes, however, the camera would not autofocus at all, in that the lens would not even attempt to adjust for focus; almost as if the camera thought it was in manual focus mode. Toggling the AF/MF switch would have no effect, however powering the camera off and on again would fix the problem.

In another strange instance, we were attempting to do a low-light long exposure shot in the lab that required around a 30 second exposure time at ISO 50. Here, we were able to set the exposure setting on the camera body itself, but the digital back seemingly ended the exposure each time prematurely -- after about five seconds or so -- therefore sending an extremely underexposed image out to the computer. This occurred despite both the camera itself and the Capture One software reporting our manually selected exposure settings. However, after shutting down the camera and removing and then replacing the digital back onto the camera, the system all worked again as expected, and we were able to capture the long exposure shots that we needed. 

Battery life on the Phase One isn't that great

For the Phase One system, both the camera body and the digital back use their own battery. And while we don't test battery life in our lab, our feeling is that the battery life on the Phase One as a whole isn't that great. The XF100 is a pretty powerful camera with lots of features and a gigantic sensor. And while there isn't a CIPA rating for the battery life, the technical support manager at Capture Integration states that we should expect around a few hours of studio shooting time with the battery pair. Of course, things like ambient temperature, enabling Live View, tethering and Wi-Fi can all drain the battery much quicker. Thankfully, in the Phase One XF100 standard kit, you get a total of four rechargeable batteries. So leave a pair charging up while you're shooting and you're all good!

Phase One XF 100 MP: Field Test Summary

All in all, the Phase One XF100 is a ridiculously good camera. The image quality is phenomenal with an incredible amount of detail, even despite the overexposing quirk we ran into. Sure, the camera is far from svelte. In fact, it weighs a ton compared to most cameras that I or anyone here at IR has held. Getting past the weight though, it's decently hand-holdable with lots of external controls and a nice contoured handgrip. However, with its massive resolution, a tripod is definitely recommended. It's also fantastically expensive, so it's certainly not a camera I'm going to pickup for my next weekend excursion. But if you're a professional photographer -- emphasis on professional -- or perhaps a deep-pocketed advanced amateur photographer, looking for the ultimate in image quality, then the Phase One XF100 is a great way to go. For landscapes, fine art, architecture, advertising and editorial work, if you need to capture the utmost in detail, then here's you camera. Just don't forget to power it on and off if you run into a jam.