출처

Sharpness 
The Fujinon XF 50-140mm ƒ/2.8 R LM OIS WR produces very sharp images, even wide open at ƒ/2.8. We do note some de-centering in our sample copy of this lens: at ƒ/2.8 the top of the image is soft at 70mm, while at 140mm the bottom is soft at ƒ/2.8.

That said, even at ƒ/2.8 the images produced are very sharp, even adding in the slight extra softness introduced by de-centering. There is barely any noticeable effect by going from 50mm to 140mm: a properly centered lens would probably only have some slight corner softness throughout.

Stopping down to ƒ/4 improves sharpness, and by ƒ/5.6 we see the lens' maximum potential: tack-sharp images across the frame. This is true all the way through to ƒ/11, where we see the beginnings of diffraction limiting, but you won't notice any practical impact on sharpness until ƒ/16. At ƒ/22 things are slightly soft throughout the frame.

개방에서는 대체로 샤프하지만 부분적으로 광축 틀어짐이 있다.f4로 조이면 더 나아지고 f5.6에서 가장 샤프하다.f11에서 회절이 시작되지만 괜찮으며 f16부터는 회절의 영향이 뚜렸하다.

Conclusion 
Fuji has produced an excellent lens with the XF 50-140mm: if you are a pro shooter looking for the 70-200mm range, you have probably already added this lens to your collection. Like most telephoto zooms, these pay for themselves quickly and become go-to lenses. Fuji hasn't skimped on quality here, and the results speak for themselves.