Fujifilm GF 45-100mm f/4: The GFX Mid-Range Zoom

The mid-range zoom is a staple for many working photographers. 24-70mm equivalent is one of those not-so-sexy-but-gets-the-job-done lenses that we all need in our bag from time to time. When it comes to M43, APS-C, or full-frame cameras, there are a plethora of options out there. In the form of the GF 45-100mm f/4, Fujifilm has attempted to address the lack of such a lens in the medium format world. So, how good is it?

For me, this lens was an investment for a particular client shoot that required high resolution and a swatch of different focal lengths. We'd be working in a dusty and wet environment, so not changing lenses was very important for us. After a few months of use, however, it has become my go-to for a lot of things. On an editorial shoot, I am now able to shoot a variety of images quickly on the GFX 50R, and as a travel lens, it performs really well. I never thought I’d see a do-it-all lens for medium format cameras, but the GF 45-100mm gets about as close as any. 

Build Quality and Handling

Fujifilm’s GF lenses come at a premium price, and as such, the company puts a lot of effort into making sure the lenses look and feel the part. In this respect, the GF 45-100mm f/4 is no exception; its all magnesium alloy and glass construction feels great in the hand. 

The rubber grips on the focusing and zoom rings feel extremely good. Much more so than some of the XF zooms like the 16-55mm and 50-140mm, they feel like they will last for a very long time. The focus ring feels mushy and has no hard stops, as we would expect. These lenses are focus by wire and Fujifilm does not seem to focus on making manual focus a pleasurable experience on the GFX system. The zoom ring, on the other hand, feels great. It has good resistance, so the focal length does not get knocked by accident or suffer from any creep. I did have a rental copy of this lens before I purchased it, and the zoom ring was much looser than mine. People treat rental gear with complete abandon here, however, so I trust that this is not a sign of things to come for my copy.

Even down to the ON/OFF switch for the image stabilization, every detail of this lens feels like you paid a couple of thousand dollars for it. I certainly hope we can start to feel more of this attention to detail in the XF lens line-up as well. 

Size and Weight

Medium format lenses have a way of becoming big and heavy, especially zooms. The GF 45-100mm f/4 is no exception to this but is not unreasonably large and heavy at almost exactly 1 kilogram (2.2 lb) and 144.5 mm (5.69”) long when zoomed to 45mm (the barrel does extend when zooming to the long end). Actually, if we’re to compare it to a full-frame lens in a similar category, it is almost 1:1 with the Nikkor 24-70mm f/2.8 VR in terms of both size and weight. 

When working with the lens on my GFX 50R, I have found that it is quite front heavy. For me, however, that’s not a problem, as I always have my left-hand support the weight from under the lens anyway. On the GFX 50S or GFX 100, the lens feels a bit more balanced due to the substantial grips on those cameras. Otherwise, it’s much like working with any GF lens except the tiny primes, so nothing much to report on it’s physical properties.

Image Quality

Fujifilm’s GF lenses have very few noticeable compromises. They have been designed to resolve beyond the current batch of sensors and, so, perform exceptionally on both the 50- and 100-megapixel offerings from Fujifilm. The GF 45-100mm f/4 is no slouch in terms of image quality and only falls slightly short of playing with the big boys like the GF 110mm f/2. 

In terms of sharpness and detail rendered, the lens is absolutely spectacular at all focal lengths and apertures. Wide-open at f/4, the corners do suffer slightly, but by f/5.6, they improve significantly, and by f/8, you’d be hard-pressed to see a difference. If I had to find discrepancies at different focal lengths, I’d say that the lens is slightly sharper at 45mm than it is at 100mm, but it is a very small difference and not noticeable in real-world use. This is all pixel-peeping, though in day-to-day use, the lens performs excellently. 

There is a vignette when used wide open that amounts to around 1/3 (45mm) -1/2 (100mm) of a stop in the far corners. By f/8 and f/11, it is all but gone and begins to show again from f/22 onwards. This is a very negligible amount that can easily be corrected if necessary. Personally, I often like to have a little shading in the corners to draw attention inwards, and this does the trick. 

During my testing, I tried extremely hard to get the lens to flare significantly. However, in the end, all I could manage was a slight reduction in contrast. No discoloration or ghosting was to be seen no matter what angle I put the sun at. This is extremely impressive for a zoom like this, so rest assured, it will take care of anything you can throw at it. 

The 9-bladed aperture produces soft and smooth bokeh that does not distract from the image at all. Since f/4 is still a reasonably wide aperture on the larger sensor, shallow depth of field is definitely possible with this lens, and I was not disappointed with how it performs. On top of that, the aperture produces beautiful sun stars when stopped down, so it’s a great option for night cityscape photography. 

Autofocus

Autofocus is excellent on this lens thanks to the linear focus motor. Although the contrast-detect wobbles are definitely present on the GFX 50S and 50R, they are all but gone on the GFX 100’s PDAF system. Even on my 50R, however, I was able to use AF-S to lock onto moving subjects quickly enough to get sharp images. AF-C, though, is a very different story. This is more of a camera than a lens issue, however, and is vastly improved on the GFX 100.

The one issue with this and all lenses I have used on the GFX system so far, is the amount of focus breathing present in the lens. As the lens cycles focus, huge changes in framing are present, so it’s a good idea to get your focus roughly dialed in before fine-tuning composition. When working on a tripod, this can be quite a painful process at times.

Image Stabilization

For those not working with the GFX 100 and its excellent IBIS system, the GF 45-100mm f/4 offers optical image stabilization built into the lens. Fujifilm states a 5-stop improvement in stabilization and notes that it will not work hand in hand with IBIS on the GFX 100.

In my testing, I was able to reliably get around 2 or 2.5 stops of usable improvement. For example, I can reliably get sharp images at the long end when using a shutter speed of 1/250 with the OIS off. Once it is switched on, however, I can easily handhold at 1/50. The same goes for the 45mm end, where I am also able to hand-hold reliably at one stop below the reciprocal. While not mind-blowing, it is certainly great to know the OIS has your back in situations where you might be working more quickly than medium format systems traditionally allow for. 

GFX 50R + GF 45-100mm f/4 @ 45mm - 1/14, f/4, ISO 800 (handheld)

One thing I would like to see added to the OIS system is some sort of tripod detection mode. On a couple of occasions, I forgot to switch the OIS off when I put the camera on a tripod. Most frames were perfect, but on occasion, the lens would seemingly detect some movement (presumably the shutter curtains tripping) and respond accordingly. Luckily, I caught it on location (thank the tether gods for this one), as it resulted in a huge loss of sharpness and even some ghosts of objects in the frame.

In the Field

The real test of a lens’ quality is how well it performs in the field. While all of the above details inform the results we can expect, how does it perform in the field? Being an all-around lens, I have set myself a couple of short assignments to get used to all of the features and idiosyncrasies of this beast as I incorporate it into my regular workflow. All in all, it's a great lens and is very versatile. The zoom range (roughly 35-80mm in full-frame terms) covers a good portion of what I shoot on a regular basis.

If anything, I'd like to see a little more on the wide end. I have found myself in a few situations where 45mm doesn't give quite enough perspective distortion for what I'm trying to achieve. Having the zoom range go out to 32mm, however, would likely have made the lens much larger and cannibalized sales of Fujifilm's other excellent zoom, the GF 32-64mm f/4. 

The f/4 maximum aperture may seem quite slow in this modern world of f/2 zooms and f/1 primes, but on the GFX sensor, it is still capable of producing shallow depth of field and really only falters in very low light. This is not a low-light sports lens, though. It is very much an everyday editorial, travel, and portrait lens. For those purposes, it does an excellent job. Would it be nice to have an f/2.8 maximum aperture? Sure. Would it be practical? Not at all.

Value for Money

Fujifilm’s GF lenses are already priced quite aggressively for the medium format world. However, with their frequent sales, you can actually get this lens for a steal when the time comes. Having said that, even at the regular price of around $2,300 in the U.S., you get a lot for your money. That's really not much more than some high-end 24-70mm lenses for full-frame cameras. 

In Conclusion

This is an excellent addition to the Fujifilm GF lens lineup. In terms of image quality, it is on par with the other fantastic offerings for the GFX system, and any small defects like vignetting are extremely well controlled. While the zoom range may not be as extensive as offerings for smaller sensors, it is still the only lens of its kind in the mirrorless medium format world. Having image stabilization built-in also makes this lens a great choice for those using the 50-megapixel bodies. For commercial or editorial work, I can see this being an excellent addition to any photographer's bag. 

What I Liked

• Excellent image quality
• High-quality build
• Variety of focal lengths
• Well priced
• Image stabilization
• Constant maximum aperture
• Fast autofocus
• Great bokeh for a zoom

What Could Be Improved

• Would love to have 32mm on the wide end
• OIS could use a tripod detection feature
• Slightly bulky on the GFX 50R, but not overly so

Purchase

You can purchase yours here.

If you're passionate about taking your photography to the next level but aren't sure where to dive in, check out the Well-Rounded Photographer tutorial where you can learn eight different genres of photography in one place. If you purchase it now, or any of our other tutorials, you can save a 15% by using "ARTICLE" at checkout.