Conclusion

The GF 45-100mm f/4 R LM OIS WR is a brilliant standard zoom lens for Fujifilm's medium-format system, offering a winning combination of versatility, stellar image quality, weather-proofing and image stabilisation.

The GF 45-100mm is a very sharp lens throughout the zoom and aperture range, exhibits almost no chromatic aberrations, has negligible distortion at either end of the zoom range, and is capable of producing some very nice bokeh despite only having an f/4 maximum aperture. Vignetting at wide-open apertures is the only real optical issue of note, although stopping down to f/8 solves the problem altogether.

The high-speed linear AF motor keeps up with the action despite having to drive a lot of glass, the build quality is once again excellent, and the traditional aperture ring is very welcome, although it sadly can't be de-clicked for video use.

Manual focusing is a veritable pleasure thanks to the massive, well-damped focusing ring and the on-camera focusing aids, while the optical image stabilisation system allows you to hand-hold the camera in much lower light levels than usual.

In summary, the Fujifilm GF 45-100mm f/4 R LM OIS WR proves itself to be a very versatile, high-quality standard zoom lens that's a real alternative to the usual medium-format choice of several primes covering a similar focal range. Along with the wide-angle GF 32-64mm f/4 R LM WR and the telephoto GF 100-200mm f/5.6 R LM OIS WR, it forms a great lens package that covers almost every focal length that you'll ever need.

Ratings (out of 5)
Design	5
Features	5
Ease-of-use	4.5
Image quality	5
Value for money	4.5