Round three of the battle between the most recent super zooms designed for mirrorless cameras takes place in the land of Fujifilm with the new XF 100-400mm f/4.5-5.6 which I rented for a week. This is an important lens for the X series because it is the first serious offering from the brand for wildlife photographers and the second lens to be compatible with its 1.4x teleconverter.
The lens also proved useful for sports as well. Coupled with the X-Pro2 and its new autofocus system, the combo delivered great results and is one of the best offerings in terms of Continous AF performance in the mirrorless realm.
The lens survived a pretty heavy storm (hail included!) and is definitely an excellent performer. However, its size and weight don’t go unnoticed which leads us to the following question:
Is the new 100-400mm a worthwhile investment for someone interested in switching from another camera system? Let’s find out!
Fujinon XF 100-400mm f4.5-5.6 R LM OIS WR Main Specs
- Focal length: 100-400mm
- Focal length (equiv. 35mm): 150-600mm
- Maximum aperture: 4.5
- Minimum aperture: 22
- Number of aperture blades: 9 rounded aperture diaphragm
- Angle of view: 16.2 ‑ 4.1°
- Closest focusing distance: 1.75m
- Lens configuration: 21 elements / 14 groups
- Special elements: 5 Extra Low dispersion, 1 Super Extra Low dispersion elements
- Maximum image magnification: 0.19x (telephoto)
- Optical Image Stabilizer: Yes (5 stops)
- Dimensions: φ94.8 Ø, 210.5 mm / 270mm
- Filter diamater: 77mm
- Weight: 1375g
Table of Contents
Below you can watch our video review of the lens.
Design and ease of use
From a build quality point of view, the XF 100-400mm feels like the best lens Fujifilm has ever designed. The construction is excellent and every ring, button and feature is easy to use.
The XF 100-400mm is weather-sealed and for once I can share some relevant feedback about this aspect. (I could have put every single camera or lens I’ve ever tested in the shower but I prefer sharing real world examples!)
I went to the Tonfanu road races for their first event of the year. The weather forecast predicted sun and showers for the entire day but nobody expected heavy storms and hail too. Seeing as I do live in Wales, I guess I need to remember that the weather can change in an instant!
What you see in the image above is just the beginning. It rained for more than three hours and the X-Pro2 and 100-400mm were soaked through by the end of the race, but they kept on working without any problem. So yes, the weather sealing is good!
Note about the X-Pro2 weather-sealing
Although this article is about the XF 100-400mm, I thought it was worth sharing the following feedback about the X-Pro2.
The X-Pro2 survived the rain very well. However, once I returned home, I noticed that two tiny water droplets had made their way inside the SD card slot. They were very tiny and close to the entrance so the memory cards remained completely dry.
I suspect this happened because during the hail storm I had to make my way back quickly (the races were cancelled in the end). I walked for 5 minutes in very heavy rain, and I was carrying the gear with my strap over my shoulder on the right side. The camera and lens were hanging in a vertical position, so the rear of the X-Pro2 was facing up. I guess the SD card door was more exposed to the heavy rain. This could be a weak spot on the camera so in extreme circumstances it is better to protect it somehow (put it under a jacket for example).
As I mentioned at the beginning, the lens is heavy and weighs more than 1.3kg. It is the largest lens Fujifilm has ever designed for the X system. I found it more tiring to hold after an entire day of shooting in comparison to other Fujifilm or m4/3 telephoto lenses. With both the X-T1 and X-Pro2, the combo can be a little front heavy.
The various rings are precise and smooth to use. The aperture ring clicks in 1/3 steps. The zoom and focus rings are covered by ribbed rubber to enhance the tactile experience. I found the focus ring precise to use despite being a “focus by wire” type. The zoom mechanism is not internal so the lens extends when zooming in.
The zoom ring is a little bit stiff near the end (longest focal length). It can be locked at 100mm to prevent the lens from extending when carried in a vertical orientation. If you don’t lock it, it can extend quite easily.
On the side of the lens you can find three switches that are common on this type of lens. They allow you to limit the focus distance to 5m-∞, set the aperture to Automatic or Manual and turn the optical stabilisation On or Off .
The lens hood is made of robust plastic. I like its lock mechanism. There is an unlock button that you need to press to remove it so you are sure that the hood doesn’t move in any way while using the lens. Like the XF 50-140mm, it has a small sliding window, which is useful to access a polarising filter.
Finally we have the tripod collar that can be rotated 360° or removed with the two dedicated knobs.
The Fujinon XF 100-400mm gives you the same angle of view of a 150-600mm if we refer to the 35mm format. It has a non-constant aperture that goes from f/4.5 at 100mm to f/5.6 at 400mm.
I found the overall optical performance to be at the same level of other professional Fuji lenses as well as other recent telephoto lenses I’ve tested. Sharpness is excellent at the fastest aperture and throughout the entire zoom range.
Let’s have a look at some simple tests to see exactly what we are talking about beginning with what interests us most. Above and below you can see that sharpness is excellent at f/5.6 already and 400mm. The peak performance is found at f/8. From f/11, diffraction starts to appear and that happens at every focal length.
Sharpness was similar at the longer focus distances too, which is where you’d be more likely to use this type of lens. Again f/8 gives you the best performance. f/11 and f/16 remain usable for panning shots if you are working on a sunny day.
I took two comparison shots with approximately the same magnification at 300mm and 400mm to see if the lens would suffer more at the longest focal length. Happily, this is not the case. I found sharpness to be very similar in both cases. The optical performance stays at the same level at 100mm and 200mm.
Note: you can see a complete comparison set here.
Long story short: you can use the lens at any focal length without worrying about a decrease in sharpness with the best performance being between f/4.5 and f/8. Diffraction is the only limit.
The versatile zoom range and the non-constant aperture usually don’t help to make the bokeh more attractive.
However I have to say that the XF 100-400mm managed to surprise me. I didn’t find too many hard edges or double images even in busy composition. Overall you get a smooth out of focus background and its capability to isolate the subject is good even at longer distances. With shorter focus distances you can encounter a slightly swirly effect which is not unpleasant.
The Fuji 100-400mm can focus as close as 1.75m through the entire zoom range. At 400mm it gives you a magnification of 0.19x (APS-C standard).
The example below shows a friendly robin at 1.75m. He was probably hoping to get some food but he got his picture taken instead!
I had to switch to manual focus because the camera couldn’t handle the situation. As you can see, sharpness remains really good at short distances too.
You can notice some very slight vignetting at the longest focal lengths and fastest aperture but it is nothing worth worrying about. I never had to deal with chromatic aberration. As for flare, if you really take the time, you can eventually find some but in most situations you won’t have to deal with it.
Single AF and short distances
While I tested the lens on the X-Pro2 mainly to get an idea of how Fuji’s new AF system performs, I also took shots with the X-T1 to give you a more complete understanding of its performance.
As far as the lens is concerned, it behaved very well on both bodies. The AF motor is fast and almost completely silent.
In single AF, the only real problem I encountered was at the shorter focus distances where both cameras struggled. The best thing to do in this case is to switch to manual focus if the camera keeps mis-focusing or moving the lens elements back and forth.
You can also encounter problems at times with busier compositions like a small bird on a tree (some back-light won’t help either). Setting the AF to a single and smaller point helps but doesn’t always solve the problem and in some cases the camera can mis-focus completely.
The best thing to do in this case is to pre-focus near the subject first so that the camera doesn’t have to change the focus distance too much when locking onto the subject.
To be fair, I’ve encounter this behaviour with other cameras I’ve tested as well with long focal lengths so I don’t consider it a major problem.
Continuous AF with the X-Pro2
The X-Pro2 and XF 100-400mm managed to surprise me on multiple occasions in C-AF. I used the gear for an evening soccer game, a motorbike race and birds in flight. Not only did it work well but it is currently one of the best mirrorless AF systems I’ve had the chance to test in these scenarios.
I always thought that Fujifilm was on the right track with the X-T1 and the X-T10/Firmware 4 but still needed to upgrade the hardware to really make a difference. This is now a reality with the X-Pro2.
I can only guess it will happen again with the X-T2 (or X-T1s or X-T1 mark II or whatever name they decide to give it!).
My favourite settings with the X-Pro2 for sports and BIF
- – C-AF and continuous shooting on High (8fps)
- – Zone AF with the largest area (BIF), largest or middle areas for motorbikes and football
- – Power management to High Performance (which gives you the 85fps refresh rate in the EVF). Be aware that the battery life will drop quickly. I had three with me.
- – Focus priority for BIF and motorbikes, release priority for football.
- – Pre-AF: Off
- – Auto ISO 1 (max. 800) for good light conditions, Auto ISO 2 (max. 3200) for cloudy conditions, Auto ISO 3 (max. 12800) for low light conditions.
I only used the Zone AF area as I find it so effective and reliable. It also allows you to have more room to compose while following a fast subject even if you are not able to keep it exactly at the centre of your frame.
For both the football game and the motorbike race, I got a keeper rate of approximately 80%.
I was particularly impressed with the soccer game. Being an evening event and the lens not being so fast, I had to use Auto ISO with the maximum set to 12800, which is the value the camera picked most of the time. Not only did I get very usable images but the AF really did a fine job and most importantly, it always had consistant behaviour even when my tracking movements were less precise.
I did end-up with some slightly soft results and at times the camera confused the subject with the background like in the example below but I don’t have lots of negative examples.
If you select release over focus priority, the AF performance remains very similar. However at times the camera can mis-focus completely and take the shot anyway if the change in focus distance is too great. To be fair, it only happened a couple of times.
The keeper rate was lower for birds in flight (around 60%) I consider that genre more challenging for the AF system. Plus, the photographer’s abilities are also relevant and I’m still an amateur when it comes to BIF.
Continuous AF with the X-T1
With the X-T1 the overall performance is slower in comparison to the X-Pro2 and I found the difference more relevant for birds in flight in particular. Note that when shooting at 8fps, both cameras use the phase detection area only but the one on the X-T1 is smaller so you end up working with a smaller AF area. That requires you to be more precise at following a fast bird which is anything but easy.
My favourite settings with the X-T1 for BIF
- – C-AF and continuous shooting to High (8fps)
- – Zone AF with the largest area (5×3)
- – Power management set to High Performance
- – Focus priority
- – Pre-AF: Off
- – Auto ISO (max. 800 for sunny, max. 3200 for cloudy conditions)
Although not related to the autofocus, I was also surprised to see the difference in EVF performance between the X-T1 and the X-Pro2.
Despite the X-Pro2 viewfinder being smaller, it has a faster refresh rate of 85fps (when you set the Power Management to High performance) and I also found the lag time between the shots to be lower when shooting at 8fps.
Speaking of viewfinders, you might be interested to read my experience using the optical viewfinder of the X-Pro2 with the 100-400mm lens for birds in flight. I know it sounds crazy but it actually works!
Fujifilm claims 5 stops of compensation with the built-in optical stabilisation and I must say the lens OIS works really well. At 400mm, I managed to get a sharp shot at 1/8s and 1/5s at 100mm with both the X-T1 and X-Pro2.
As usual in the real world, remember that a higher shutter speed will always ensure more sharpness when shooting at 300mm or 400mm. Plus no matter how still you are or how good the OIS is, your subject might not want to pose for you for too long. I got some slightly blurry shots even at 1/250s or above.
The OIS is also effective for video. You can watch an example in our video review at minute 9.22.
The Fuji 100-400mm + XF 1.4X Teleconverter
With the 100-400mm lens I also rented the 1.4 teleconverter. It is the second lens to be compatible along with the 50-140mm f/2.8. The focal length becomes 140-560mm which is equivalent to a 210-840mm in 35mm format. The fastest aperture becomes f/6.7 at 100mm and f/8 at 400mm.
Concerning the optical performance, there is a slight loss in sharpness. It is not huge but it is worth mentioning. The best performance is once again at f/8 and that aperture becomes the best way to get the best sharpness possible.
Once again I tested it on both the X-Pro2 and X-T1. With the teleconverter the autofocus performance was slower on both cameras. The cameras can take more time to lock onto the subject and can be less accurate especially with birds in flight.
The best results I got with the 100-400mm and TC 1.4 was at the motorbike race. The converter is also weather-sealed and survived the same horrid conditions without any problem.
The XF 100-400mm is an excellent lens as far as optical quality is concerned. I wouldn’t go as far as saying that I was impressed but I felt it was at the same level as other premium telephoto zooms and on par with the quality Fujifilm has given us already with other zoom lenses such as the XF 16-55mm and XF 50-140mm. The optical stabilisation does an excellent job and the AF motor is fast. Coupled with the X-Pro2, I got some of the best results ever in Continuous AF.
The only real argument worth mentioning (but not necessarily in a negative way) is the size and weight.
It definitely felt closer to a DSLR lens. We could compare specs and notice that a Canon 100-400mm is still a little heavier but sometimes personal feelings are more important than numbers on a specs sheet.
In a way I am not surprised because this is where mirrorless systems are going lately. The brands are releasing high quality lenses that require more volume for various reasons. The reasoning here can be seen from two sides.
If you are already a Fuji customer and were waiting for a high quality lens with a long reach for wildlife or sports photography, this is the only real choice you have so the discussion ends here.
However if you are looking into an alternative to a DSLR for wildlife photography, I think the difference is less relevant. The price is on par with other lenses of this type (nearly $1900) so you won’t gain anything there, and there is also the fact that for now the best match is the X-Pro2 which is quite expensive. Yes, the Fuji combo is lighter but perhaps not as light as you might hope (and the Fuji lens is actually slightly longer than the Canon equivalent). Yes, the AF on the X-Pro2 has improved considerably but I bet it isn’t superior to a 7D mark II. Plus there is another aspect to consider and that is the viewfinder position. I admit that I find the EVF at the centre more comfortable to use. I guess we can continue this topic once the X-T1 successor is out!
What I like about the Fujifilm 100-400mm f/4.5-5.6:
- Top notch build quality and weather sealing
- Excellent sharpness throughout the entire zoom range and fastest apertures
- Good bokeh rendering
- Good optical stabilization
- Fast AF motor with both X-T1 and X-Pro2
What I don’t like about the Fujifilm 100-400mm f/4.5-5.6:
- Large and heavy on most Fuji camera bodies
- The zoom ring is a little bit stiff at the longest focal length (at least on the sample I rented)
- Diffraction starts from f/11 (but remains acceptable up to f/16)
What can be considered about the Fujifilm 100-400mm f/4.5-5.6:
- It might not be the best solution for someone looking at a lighter or less expensive alternative for wildlife photography.
The Fuji 100-400mm vs. similar offerings from other mirrorless systems
As I wrote earlier, the XF 100-400mm’s sharpness didn’t impressed me in comparison to the Olympus 300mm Pro or the Pana/Leica 100-400mm. However I did find the overall set-up with the X-Pro2 slightly better in terms of overall image quality (larger sensor, more resolution) and the possibility to separate the subject from the background. It’s not a huge difference but worth mentioning.
I definitely got some of my best shots of birds in flight with the X-Pro2 but in total honesty, it is also because I’m getting used to it more now and I’ve improved thanks to my experience testing these lenses. The next on the list is the Sony a6300. Stay tuned!
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