There has always been a gap between DSLR and Medium format digital cameras, but that gap has now been narrowed, first by the Canon 5DS R and since the Nikon D850. We have been using both cameras side by side with high-end medium format digital cameras. The autofocus hit-rate is considerably better and the cameras are overall snappier. You get a lot of camera for your money, but keep in mind that shooting with the Canon 5Ds R or D850 requires that you step up your technique. In other words, the subject blur and camera shake that sometimes would be unnoticeable when using a lower Mpix camera will reveal itself immediately when using a 50+ Mpix camera. We now only recommend MFD to our clients when they need the outmost in image resolution and file integrity.
Another issue we recently noticed occurred during a shoot that included 2 rented cameras from a local rental house. Both cameras back-focused about 3” leaving the model’s eyes consistently out of focus. Technical issues always involve a bit of playing catch-up especially when you’re on set. They’re difficult to correct on the fly, and before you realize the problem and deem it serious enough to use time on, you could be an hour or so into your shoot. That’s why we always recommend renting cameras and lenses from us. We simply know our cameras and have already ironed out all the kinks.