Lenses Combining High Magnification and High Image Quality「XF18-120mm」

XF18-120mm, the key word is “unchanged.

As the name suggests, the XF18-120mmF4 LM PZ WR covers 6.7x from 18mm to 120mm (27mm-183mm in full size) and has a f/4.0 release in the entire range. Also, the abbreviation PZ stands for power zoom. However, it does not have in-lens image stabilization.

In a word, the keyword for this lens is symbolized by the word “unchanging.

To solve this “unchanging” problem optically or mechanically would require tremendous technical capabilities and cost. By making it electric, we have succeeded in making it small, lightweight, and inexpensive.

In the case of moving images, the fact that the aperture remains the same is of great significance.

I am sure you can understand that there is no substitute for the fact that the aperture value remains the same. In video, we do not want to change the shutter speed or sensitivity, so if the aperture value changes depending on the focal length, we end up having to consider the darkest aperture value as the standard. The ability to use f/4.0 as the standard aperture value makes it easier to shoot and improves the quality of the video.

What is most exciting is that the overall length of the lens does not change when the lens is set to inner focus. One of the advantages of using a mirrorless camera is that gimbal shooting can be done easily. However, if the lens length changes, you have to re-balance the camera position front to back each time. If there is lens expansion or contraction due to zooming, the gimbal’s motor power can be used to adjust the lens to the middle value and somehow get by, but there is no substitute for the sense of stability when the camera is balanced.

In addition to the gimbal, another advantage is that when the mattebox is mounted on a sliding base, there is no need to rearrange the mattebox position depending on the lens extension.

Still lenses shift their focus position when zoomed. I thought that was unavoidable. The X lenses up to now have done a clever little thing by refocusing at a fixed moment when the angle of view is adjusted by zooming, even when the lens is in manual focus.

This is a movement to compensate for the focus misalignment, which is unavoidable due to the structure of the lens, by casually correcting the focus by electronic control. The XF18-120mm compensates for the focus speed so fast that you do not feel like you are working underwater, and the fact that the focus position does not shift exactly when zooming with manual focus broadens the range of shooting methods.

Breathing is a reduction in the angle of view change that occurs when adjusting focus, and lens developers are working hard to suppress it. Despite such efforts, the sad fact is that lenses with suppressed breathing are rarely appreciated because they are unconsciously accepted by users.

In particular, the inner focus mechanism used in the XF18-120mm tends to produce significant breathing. While there are many models that take advantage of the oversampling resolution to solve the angle of view adjustment by image processing, it is amazing that the change in angle of view due to this bleeding is solved optically by adjusting the zoom, taking advantage of the characteristics of a motorized zoom lens.

It may seem obvious that the central axis does not change even when zooming, but it requires a great deal of precision to achieve this. Originally, the mechanism of a zoom lens was to change the distance between the lenses and the angle of view by turning the lenses like a rotating screw. However, the XF18-120mm uses an axis-suspended structure, which allows the lens to move back and forth by a motor without rotating.

In fact, the E PZ 18-105mm F4 G OSS, which Sony released nine years ago as the first G lens on the E-mount, uses the same axis-suspended structure. This lens, which is considered a hidden masterpiece and is back in the limelight with the introduction of the FX30, is surely modeled after the XF18-120mm. After all, the model is 9 years old, so it is not difficult to imagine that it was a proposition to surpass the E PZ 18-105mm F4 G OSS in every respect. However, I don’t dislike the style of jumping into this genre that was created 9 years ago and had no followers, just as if the time is ripe.

After all, thanks to this technology, focus, breathing, and center problems have been solved, so it is a mystery why it was not popularized before.

Amazing power zoom

While the various benefits of electrification are being enjoyed, there are some factors that must be taken into consideration when making videos because of electrification. That is “sound. However, even in the video shot at the fastest constant-speed zoom, the sound of the zoom motor was not recorded by the camera, even though it was recorded with the camera’s own microphone. Unless you are in a silent situation, you will not be bothered by it.

To tell the truth, I myself was not comfortable with the power zoom. The power zoom I had used in the past seemed to be operated by a lever as the main control system and the zoom ring could be operated manually, and I had the impression that the operation was a little out of sync with my hand.

For example, when the image stabilization is applied very tightly, you may shake the camera and think, “I’ve got it right here! but then the movement of the camera follows and the angle of view is too far from the one you have set.

This is what surprised me when I tried it this time. I had the impression that the camera would follow even the slightest movement of my finger, and when I stopped, it would stop exactly as I had stopped, and even fast movements that can be performed with a normal hand would follow without discomfort. The XF18-120mm has removed my prejudice against power zooms.

The advantage of the power zoom is that you can choose between clockwise and counterclockwise rotation. I am familiar with the concept of FUJINON clockwise being telephoto and counterclockwise being wide-angle, but Canon and Sigma people may feel more comfortable with the opposite. It is probably only a power zoom that can enter into such a situation without discomfort.

Unique power zoom operation

Of course, there are several other controls that are unique to power zooms.

The standard operation is the zoom lever located on the body side of the zoom ring. This is a standard operation that changes speed in 256 steps depending on the degree of pressure, and there is no problem with the smooth operation of this operation, as you will not feel any change in speed.

Another notable feature is the low-speed zoom button on the body side, which has two buttons, Tele and Wide, that start zooming at a constant speed with a single press. There are eight speeds available, with the slowest (1) taking approximately 1 minute and 38 seconds to zoom from the Tele end to the Wide end. This is not a feat that can be done by humans.

At the fastest speed of 8, it takes about 10 seconds to go from the widest angle to the furthest distance. I am glad that I don’t have to keep pressing the button. Pressing the button again or performing any other camera operation will release it.

The Z/F button above it is a switch button that assigns the zoom lever to focus. However, for me, who feels more comfortable using the focus ring on the tip of the camera to send the focus, this function is a bit of a “what? However, the big advantage of this button is that you can assign various functions to it. You can assign AE lock, AF lock, or face recognition on/off, but it will be useful if you choose one that suits your shooting style.

The same operations that can be performed on the side of the lens can also be performed from the rear LCD. You can control the constant speed as well as the movement of the variable zoom lever.

It is rare to operate this zoom action from a touch panel, but if this is possible, we can expect variable speed zoom work when remotely operating the camera by using the FT-XH file transmitter, which will be on sale soon. According to Fujifilm’s announcement, up to four cameras and lenses can be remotely operated (wired/wireless LAN) from a PC, so the XF18-120mm will be the main lens when it comes to remote operation for event photography.

Whatever the case may be, in the end, it all comes down to whether the images taken with this lens are beautiful or not.

F-log and F-log2 with children as subjects

This time, I chose my own son, who I have the least control over, as my subject, and shot with both F-log and F-log2. the combination of X-H2S and XF18-120mm had a good AF and kept tracking my child who was moving in all directions. When I checked the image during editing, there were some areas where the focus was in the background in places, but there was no breathing and the focus behavior was not very quick, so I don’t think it would bother me in a snap shot.

The only time I had a problem was at 18mm, which is included at the end of the zoom test video I linked to at the beginning, when panning through the trees, where I had to move back and forth between infinity and close range in a fast motion, but other than that, I felt comfortable with the manual zooming feel.

As for the recording media, we were able to borrow a CFexpress TypeB 650GB COBALT 1700R and a card reader from ProGrade Digital, making it possible to record in 4K ProRes 422 HQ. The CFexpress TypeB is the only media that can record in the highly versatile ProRes format for editing. 650GB is only enough for a little over 2 hours of 4K ProRes 422 HQ recording, so if you want to record in ProRes, you will need a high-capacity CFexpress TypeB.

ProGrade DigitalのCOBALT 1700R 650GBは、8K、6.2K、4KのProRes/ProResHQ記録に対応する

The recorded material had a resolution and color tone that could be said to be that of a Fujifilm. I like the colors so much that I continue to use the X-T3 in combination with XF lenses, and considering that I often choose Alura and Premista lenses for commercials and other shoots, Fujifilm’s sense of color tones may be to my liking.

How about a f/4.0 release value?

However, what you may be concerned about is the f/4.0 release value. With the current situation where high sensitivity has become so beautiful, I think that the F4.0 value is not so much of a problem in terms of brightness. Incidentally, this time I tested the X-H2S from ISO 1250 to ISO 12800 in stages using F-log2, but the image quality degradation was only a slight change, and I had the impression that ISO 12800 could just barely withstand use (the HLG results I used for testing were good, and I felt it had more potential than F-log2).

Many people are more concerned about depth of field than brightness. Compared to full size, APS-C (Super35 angle of view) has a wider range of focus, which is difficult to achieve unless you use a so-called movie SLR and a single focus lens, like a portrait-like single focus with a f/1.4 release or something, where only the subject is in focus and the background is fantastically blurry! The background is fantastically out of focus.

High-power zoom does not sacrifice image quality

However, this zoom is high enough to work well as a video camera. I occasionally shoot with a camcorder with a small sensor lens, but I am less and less satisfied with the image quality when it comes to 4K and higher resolutions. It is to embed a large number of pixels in a small sensor, both in terms of sensitivity and latitude. Considering this, the combination of X-H2S and XF18-120mm, which has no shooting time limit, can be expected to be used as a video camera.

At live music clubs that have started video distribution since the Corona disaster, we often see one-man operation with 4 camera switching. In such cases, a system that can be remotely operated at this magnification is likely to be able to construct a system that can provide higher quality video than a small sensor with a narrower latitude. If you could include a super resolution zoom that takes advantage of the high resolution of the sensor, you would get performance comparable to a 20x class zoom lens, but I wonder if this would not be added in a firmware update?

With the X-H2 having 8K resolution, Fujifilm has announced a new 40MP recommended lens. Of course, this XF18-120mm is in the lineup (the fact that my own XF55-200mmF3.5-4.8 R LM OIS is sadly missing from this list suggests strict criteria).

Also, I used it with the X-H2S this time, but when I first used it with the X-T3, the behavior was terrible. After updating the X-T3 to the latest firmware that was recently released, the behavior of the lens is now equivalent to that of the X-H2S. It is possible that you will not be able to enjoy this feature without the latest firmware, so please refer to the compatibility chart before you get it.

For myself, I thought it was inevitable that all-in-one zoom lenses would sacrifice image quality. In any case, a lens like the XF18-120mm, which can handle everything, is considered a location hunting lens, and the standard practice was to prepare a single focal length or a low-power zoom lens to cover the angle of view you had decided on.

However, technology has enabled lenses to overcome the weaknesses of such lenses, and lenses that combine high magnification and high image quality have emerged. Now I may have to overcome this belief that “ease of use = lower quality.