Phase One medium format systems are a mix of old-school design and bleeding-edge technology. Its IQ4 150MP ($ 51,990 with XF body and lens) includes an image sensor that’s just about as large as a frame from a 645 film camera, with more pixels than we’ve seen in any consumer model to date, but doesn’t handle quite as well or focus as quickly as some of its upstart competition in the mirrorless world. Even with the caveats, its imaging capabilities are class-leading, and it will slide right into workflows that already utilize Phase One hardware, and earns our Editors’ Choice award for high-end medium format systems.
The IQ4 Family
There’s also the IQ4 150MP Achromatic, which is the upgraded version of the IQ3 100MP Achromatic and has a sensor that captures black-and-white photos exclusively. The IQ4 100MP Trichromatic doesn’t have as many pixels—its sensor is the same as the IQ3 100MP Trichromatic, which has a stronger Bayer filter for truer colors and a lower native ISO.
The IQ4 back has the same basic design as the IQ3—a modular brick which attaches to the back of an XF (or other) camera. It retains the same basic interface—four physical buttons and touch input support—but swaps the aging Compact Flash memory format for dual XQD and UHS-II SDXC slots, and now uses USB-C or Ethernet for tethered shooting. One quirk of note—you will absolutely need to use an XQD for non-tethered shooting, as the SD slot is only used as a real-time backup. Phase One includes a pair of 64GB cards, one XQD and one SDXC, with the kit.
Tethering over Wi-Fi is also an option, so you don’t have to plug a cable into your computer to get it going. I tested it with a MacBook Pro and Capture One Pro 12 and my 802.11ac home network (peer-to-peer connections are not an option). I was able to connect to my 5GHz network by selecting it from the camera’s screen and typing in the password. The on-screen keyboard is a little tight and I had to use the backspace button a few times, but once it was set up, the wireless tethering worked.
Speed is a big concern for tethered operation, and it’s an issue when working wirelessly. There’s about a 15-second delay between making an exposure and its appearing in Capture One. With a wired connection, there’s no delay. But you do get the option of showing a live feed from the sensor on your computer screen with no lag of note, just as you would with a wired tether. The IQ4 doesn’t work with the iPad control app at press time—its support is limited to the IQ3 generation.
The XF Body
The XF is a relatively recent body design—it was introduced along with the IQ3 series in 2015. It’s a big SLR—it measures 5.3 by 6.0 by 6.3 inches and weighs about 4.6 pounds with the back, but no lens, attached. You get any lens you want with a kit—the 80mm is the standard option and weighs a little more than a pound.
The system is delivered in a rolling hard case with two inserts. One houses the camera, lens, memory cards, and a couple of spare batteries. It also includes a license for Capture One Pro 12 (printed on a hard plastic card) and a warranty card—Phase One covers the system for five years, and as you’d expect for the price, includes loaner coverage if your kit does need to go in for service.
The second insert includes separate pouches for accessories, cables, and power. If you’ve owned Phase One systems in the past, you’ll remember that the battery charger was a bit dated in design—overly large and with a clumsy hinged stand. The IQ4 uses the same batteries, but includes a new compact charger. Its footprint is only a couple inches on each side, and it offers the convenience of charging two batteries simultaneously via an AC or DC (over USB) source.
Both the IQ4 back and XF body house a battery, and the kit ships with four. Power is shared between the two components, so a depleted battery in one slot won’t keep you from shooting. Battery life will depend on how frequently you’re making exposures, but I found one set would get me through a few hours of photography with plenty of room to spare. If you’re often working on location, away from power, it’s wise to bring a few extra sets along.
The XF body has a pair of programmable buttons, one on the front and one on the rear, along with dedicated control dials for ISO, aperture, and shutter speed. The body has an OLED touch panel on the top plate, which gives access to menus and other camera settings. You can swipe to show an in-body bubble level, access bracketing settings, set the intervalometer for time-lapse, access macro focus stacking, and control Profoto lights. There’s even a built-in seismograph which shows vibrations as they happen, and can trigger the camera to fire when vibration has subsided—sometimes necessary to get the most detail out of the 151MP image sensor.
By default the back shows an information display with the current exposure parameters, all of which can be set by touch. The IQ4 back and XF communicate, so any changes to settings you make via the body controls will be reflected on the IQ4’s screen. Likewise, you can adjust any XF body settings via the back’s larger screen.
The touch interface isn’t the most intuitive, but you’ll get the hang of it. Swiping down from the top shows battery, network, and memory card capacity. Swipe from the right side and you’ll display a big digital spirit level, a boon for landscape, architectural, and technical applications. Swipe up from the bottom to bring up a screen that gives quick access to exposure controls, live view, playback, and the menus.
There are some things about the interface that could use a little bit of work. Tapping the IQ4 back’s top-left button, for example, toggles between capture and a few different image playback screens. But despite showing big, touch-friendly icons when pressed, they aren’t sensitive to touch. It’s a minor thing, just like the on-screen keyboard being a little too tight to comfortably type in my Wi-Fi network password (for tethering setup). And, despite having four physical buttons available on the back, none of them take you directly into the menu. Phase One is no stranger to improving functionality via firmware, and there’s nothing here that can’t be fixed with an update.
Autofocus Speed and Burst Shooting
If you’re used to cameras that power up and focus instantly, the IQ4 is going to be be a big shock to your system. It’s not a fast camera in focus or startup speed. It requires about 19 seconds to power on and get ready to shoot. There is a 0.4-second delay between pressing the shutter and making an image, even when the lens is set to manual focus.
The XF autofocus system is simplistic. There’s a central focus area, so if you want to focus on an off-center subject you’re limited to recomposing your shot after a focus lock, or focusing manually. It’s a far cry from modern mirrorless medium format cameras, like the Fujifilm GFX 50S, which start and focus faster, with the ability to put a focus point in almost any part of the frame. But it’s similar to what you get with the IQ4’s closest competitor, the Hasselblad H6D, currently available in a 100MP version for $ 32,995.
Continuous shooting speed is important to certain disciplines which the IQ4 is well-suited—fashion photography is the obvious example. The shooting speed varies based on the quality of images you’re recording. At its default setting, where the IQ4 shoots 14-bit compressed Raw images, the IQ4 fires off shots at a modest 1.4fps, a pace which it can keep for 44 shots before slowing down. Fully clearing the buffer to memory takes about 80 seconds, not surprising as each image is around 100MB in size.
For applications where absolute image quality is imperative, the camera’s highest 16-bit quality setting is an option. It does slow down continuous shooting, dropping speed to about 0.7fps with enough space in the buffer for about 20 images—the typical 16-bit Raw image is about 200MB in size. All speed tests were performed using dual memory cards—a 400MBps XQD card and a 299MBps SDXC card, both from Sony.
Manual focus is likely to be used with the XF for many applications. All the resolution in the world won’t do you much good if your image is out of focus. The eye-level viewfinder offers a big view of the world, but I wouldn’t rely on it for critical focus. Instead, the view from the rear LCD is really what you want to use. Set the camera on the tripod, punch in and magnify the portion of the frame you want to be in focus, and set the lens manually. Focus peaking is also an option, and peaking even shows on your computer’s screen when tethering.
The body features a focal plane shutter (with 1/125-sync), but you’ll typically only use it when paired with a lens without an integral leaf shutter. When shooting from live view, there’s a fully electronic shutter option for vibration-free capture, but there’s also mirror lock-up in the body to avoid vibration when using the in-lens or focal plane shutter. Leaf shutter lenses sync with strobes for exposures as short as 1/1,600-second.
I tend to like working a bit low to the ground, which does present a challenge. The IQ4’s screen doesn’t offer any sort of articulation, so if you want to manually focus a shot from ground level, you’re getting down on the ground. I found myself laying on my stomach to get shots perfectly framed and focused, where I wouldn’t have to get quite as familiar with the earth when using a camera with a tilting screen and a slicker autofocus system, like the Fujifilm GFX 50R. A waist-level finder is available for the XF body, and is a good add-on if you like work from lower angles.
The Most Pixels
I’ve mentioned both the Fujifilm GFX 50S and 50R, which are much more affordable medium format cameras. But, as you’d surmise from the model name, they both pack a more pedestrian 50MP image sensor—a third of the pixels found in the IQ4 150MP. They also use image sensors which are physically smaller—the Fujifilm models use a 33-by-44mm sensor, while the IQ4 150MP spreads its pixels across a 54-by-40mm area—about a 50-percent increase in surface area.
Just how much detail is there in a 150MP image? Take a look at the image above, resized for the web, but representing the full view of the lens. I was shooting blind, with the camera pointed in the general direction of the two mallards swimming close to shore, but the autofocus system found the wood duck, just about dead center in the frame, instead.
The image above is a pixel-level crop. It’s taken from what is, to my eyes, the sharpest point of focus, which is on the wood duck. Even given the rather paltry area of the frame the drake occupies, the IQ4 150MP picks up quite a bit of details in his feathers. It’s just one example. In another, I captured an insect passing through the frame when photographing some spring blossoms. Out of context there’s not much to it, but it’s one of those small details you’ll notice in a print—assuming you don’t decide to use a spot removal tool to take the photobombing bug out of your shot.
It’s not all about resolution, of course. The sensor also captures an incredible amount of dynamic range. I was able to dramatically underexpose images and make them look like I had nailed the exposure in camera with a few slider adjustments in Capture One Pro 12. Likewise, there’s plenty of room to rein in highlights (we typically use Lightroom Classic CC as a Raw converter, but Adobe doesn’t support the IQ4 at this time).
In terms of sensitivity, the IQ4 150MP sensor can be set as low as ISO 50 and as high as ISO 25600. I used Imatest to analyze the noise output from Raw images, converted with no adjustments made in Capture One Pro 12, and rendered in TIF format for evaluation. The sensor shows very little noise at lower ISO settings, keeping it under 1 percent through ISO 400. Cropped images from the detail portion of our test scene, a foreign banknote, show that there’s absolutely no loss of image quality when moving from ISO 50 through ISO 400.
Image quality remains superb at ISO 800, with no visible loss in fine detail. We see very slight smudges at ISO 1600, but only when viewed at full magnification. Grain is more apparent starting at ISO 3200, and it starts to blur very fine lines together at ISO 6400. I’d still feel comfortable shooting at ISO 12800 if needed, but would caution against pushing the camera to its top ISO 25600 setting. There’s more loss of detail there.
New to the IQ4 is a JPG engine. That’s a pretty weird thing to think about, given the ubiquity of the format. It’s not a feature you’ll ever use—the camera’s JPG output is 1.9MP (1,600-by-1,200), and can only be saved to SD. Turning it on disables the ability to write to the XQD and SD card simultaneously.
While it’s not tied to the JPG engine, Phase One is advertising the IQ4’s Capture One Inside function. It is not in-camera Raw processing like you get with the Fujifilm GFX series. Instead it allows you to select a Style (Capture One’s term for develop presets) and apply it to images as they’re captured. Style choices include Default, Landscape, IQ Professor, Still Life, Fashion, B&W Neutral, and B&W High Contrast. Once you’ve shot an image with a Style it’s locked in as far as on-screen playback goes, but the Raw file can be edited as freely as any other in the desktop version of Capture One Pro.
In a Class By Itself
You don’t have a lot of brand options when shopping for digital medium format gear. In addition to Phase One, Hasselblad is the only other company making a modern system with a removable back. It has a 100MP model, the H6d-100c, but has yet to make any announcements regarding a version with the Sony-made 151MP image sensor. It does have a high-resolution model, in the form of the H6d-400c ($ 47,995). It requires multiple exposures to output at 400MP, making it a very specialized tool.
Other medium format options are restricted to the smaller 33-by-44mm sensor size. It’s what Pentax uses in the aging 50MP 645Z and what you get with the mirrorless Fujifilm GFX 50R and 50S, as well as the mirrorless Hasselblad X1D. They cost a lot less, and have more advanced autofocus systems as a rule.
They don’t punch in the same class as far as resolution, but that won’t be the story forever. Fujifilm is developing a 100MP camera, based around its GF lens system and the 33-by-44mm sensor size. Full details aren’t out, so we don’t know exactly what it can do or will cost, but the company promises to improve focus speed via the use of phase detection, and it will include in-body image stabilization, something we’ve not yet seen in the medium format world.
We’re naming the Phase One IQ4 150MP as our Editors’ Choice for high-end medium format gear. Its resolution is unparalleled—as long as you don’t count the black-and-white-only IQ4 150MP Achromatic. It also includes a strong support package, which is important for working photographers for whom downtime equates to a loss of income. Phase One may face more serious, lower-cost competition in the future, but for now the IQ4 150MP is peerless.