Autofocus and video

Though the GFX 50R's autofocus system can use single autofocus with good speed given enough light, the contrast-detection system isn't the best choice for tracking any action faster than pedestrians.
ISO 200 | 1/450 sec | F2.8 | Fujifilm GF 63mm F2.8
Photo by Carey Rose

The autofocus system on the GFX is contrast-detect, and is generally speedy given enough light and also highly accurate. However, relying solely on contrast detection means that we can't really recommend using the camera in continuous autofocus, as the hunting can be very distracting.

Key takeaways:

  • Impressive focus accuracy
  • Focus speeds vary greatly depending on lens used
  • Good viewfinder and excellent magnification aid manual focusing
  • Continuous autofocus not recommended; pre-focusing and anticipating moving subjects is a better bet

In depth

The GFX 50R's contrast-detect AF is better suited for still subjects than it is moving subjects. Edited to taste in Adobe Camera Raw.
ISO 100 | 1/60 sec | F4| GF 45mm F2.8 R WR
Photo by Scott Everett

From the user's perspective, the GFX 50R has essentially the same autofocus implementation as the company's X-series ILCs. The big difference is the performance. This is partly because the GFX has no phase detection elements on its sensor, so has no awareness of depth, leaving it dependent on contrast-detection (essentially a rapid trial-and-error approach). It's also likely to be the result of its large lenses having large glass elements to move around. This additional mass means greater inertia, which is the enemy of fast focus, especially with the constant direction changes needed for contrast-detect AF.

There are three AF area modes:

  • Single point (manually select from either 117 or 425 points, of adjustable size)
  • Zone (manually select a zone covering a number of AF points, variable size)
  • Wide/Tracking (Let the camera choose the AF point in S-AF, specify a subject to track in C-AF)

The greatest benefit of contrast detection is that it can be supremely accurate, since it uses the view through the lens to assess the focus distance that gives optimal sharpness (though there's still a risk of mis-focus if the camera focuses a lens at a different aperture than the one you take the photo with).

Face/Eye-Detection

On top of this is a Face/Eye detection mode, which overrides the AF area mode you've chosen and focuses on a face or eye in the scene. If you have more than one face in the scene, there's no way of specifying which one you want the camera to focus on. The eye detection aspect (that let you select left, right or automatic eye selection) is not very good at detecting eyes and readily loses them. Given the expectations of medium format photography and the level of scrutiny it allows, we found a single, manually-positioned AF point was a more reliable way of shooting posed portraits.


Video

The GFX 50R can shoot 1080 video at up to 30p and can do so for up to 29 minutes, 59 seconds. It's captured as H.264 MOV files at a bitrate of 36Mbps. Unfortunately, because its large sensor is relatively slow to read-out, it will exhibit a considerable amount of rolling shutter. The footage is also achieved by line-skipping, so isn't especially detailed, either.

It probably won't come as a surprise to find the GFX 50R is not a camera we'd recommend for video shooting. That said, in terms of detail capture, it's not exactly far behind some other contemporary video-capable cameras in full HD.