dpreview just pubished the full interview with well known Fujifilm Manager Toshihisa Iida. They talked about the Fujifilm GFX. Among the others T. Iida says here:

• APS-C is more speed, more portability – that’s our X-series. And our medium-format is for ultimate image quality.
• Fujifilm GFX: The challenge is how to get the light hit the sensor evenly – in the center and also at the corners. In order to achieve that we customized the microlenses . […] Also we optimized the silicon process. We spent a lot of time and resources on this kind of customization.
• The challenges [of recording 4K Video] for every manufacturer are power and heat. And there are two ways minimize their impact. One way is to make the camera bigger. The second way is to make the video file smaller, by recording video from a cropped area of the frame. We think that it’s important to pursue the ultimate in quality, so on the X-T2 for example we tried to minimize the crop factor. Some manufacturers are offering crops of 1.5 X or 1.7X. This doesn’t help photographers at all.
• We designed these new lenses to be future-proof. The potential resolution of these new lenses is much higher than 50MP. Our benchmark is 4700 line pairs. So the lenses can resolve at least 100MP.
• Probably, in 2 years time, the size of the mirrorless market will exceed the market for DSLRs, globally.
• The smartphone is not the enemy, it’s a complement to a camera. And how to enable connectivity between a smart device and our cameras is very important. We will focus on making it faster, smoother.

You can read this and much more in the dpreview interview here. They also gave us a more precise idea of when the GFX will hit the market. According to dpreview it will be spring (so late March/April at earliest)

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