Notes:

• This article is a work-in-progress and will be updated from time to time. So far, updates have been added on January 19, 2018 (some printable test images) and January 28, 2018 ( a report on the Fujifilm 32-64mm lens).
• Speaking of updates, you may be interested in a companion update that includes more test files: Fujifilm GFX and Canon 5DsR Part II.
• When I originally posted there was only one Fujifilm GFX camera using a miniMF sensor, the 50S. To streamline things I simply referred to the “GFX.” Now (November, 2018) that there is a second model, the 50R, unless otherwise indicated I am referring to the original 50S model in this article. I have updated it to be more specific. (And as of May 2019 there is a third! Fujifilm just announced the 100MP GFX 100, an interesting — but expensive! — 100MP miniMF system. 
• And, of course, time and Fujifilm march onward. As of June 2022 the GFX 100 actually exists, along with a newer and smaller GFX100s, and an improved version of the 50s is available. And now, in mid-2024, there are more new models. The GFX 100 is now the “II,” and the GFX100s has been updated to the GFX 100s iI. All still use essentially the same 100MP sensor, though other aspects of design and functionality have been updated. In addition, there are now more G lenses for the GFX cameras, though there cold be more! On the Canon side, the mirrorless R models now predominate, but Canon has not seen fit to update their high MP sensor beyond the 50MP of the 5DsR. For a while there were rumors of a 80MP sensor “R5s” camera, but recently there have been no updates about this.

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I have been intrigued by the potential of medium format digital cameras for perhaps the past decade or so, and recent smaller and less expensive miniMF digital cameras have piqued my interest. I have friends who use these cameras, and we have carefully compared prints from them and discussed their pluses and minuses. I remain intrigued, and I may eventually move in this direction, though for now I have decided to be patient. (For a summary of my thinking, see a recent article here at the website: Mini Medium Format… Or Not?.)

Before having an opportunity to use miniMF gear, my hypothesis regarding image quality was that:

miniMF should be able to produce better image quality than a full frame camera with similar pixel resolution, but the difference is likely to be relatively small. 

Later on in this article I may be able to offer some useful, though somewhat less than rigorously scientific, evidence for this point of view.

A couple of weeks ago I had the opportunity to shoot my Canon 5DsR DSLR side-by-side with the Fujifilm GFX 50S, thanks to my friend Jeff Vadasz, who had rented the Fujifilm body along with the Fujifilm GF 32-64mm f/4 R LM WR wide-angle lens. Given time constraints (I had just returned from a week on the East Coast, and Jeff’s time with the camera was almost over), I did not have an opportunity to do comprehensive objective tests — but I was able to handle the camera, use one of the lenses that interests me, and make a series of side-by-side comparison photographs with the Fujifilm rig and my Canon 5DsR with the Canon EF 24-70mm f/2.8L II lens. Given the informal nature of this experience, regard what follows as being more of a “report” of my impressions than a formal review. (You can find plenty of test-filled formal reviews online.)

Also, regard this report as a “work in progress” — I plan to add additional material as I have time to prepare them.

Fujifilm GFX 50S ergonomics and handling

Traditional medium format (MF) cameras are pretty big and bulky, at least by comparison to current full-frame and cropped sensor DSLRs and mirrorless cameras. Early digital medium format camera systems were equally large, since they often simply replaced the MF film backs with digital backs. Eventually some manufactures began to incorporate the sensors directly into camera body, reducing the size of the system and presenting other advantages.

The introduction of the Pentax 645d in 2010 was a watershed moment for digital MF. (The Leica S2, with its 30mm x 45mm 3:2 aspect ratio sensor, arrived a couple of years earlier, though it never became widely popular.) This Pentax camera, and its eventual successor the 645z, used a 33mm x 44mm miniMF sensor, a size roughly midway between digital full-frame (and 35mm film) and the 645 film format, the smallest of the traditional common medium format film formats — larger than full-frame but smaller than film medium format. The Pentax cameras, with their reflex design, have a distinctly retro look, with shape, size, and handling suggesting the older film medium format cameras — in other words, they are larger and more unwieldy than modern full frame cameras.

Body Size

The Fujifilm GFX 50S is much more compact than these previous digital MF and miniMF cameras, largely due to the mirrorless body design, which eliminates the mechanical reflex mirror system. (It also eliminates a number of moving parts.)  The result is a camera whose bulk and weight will feel familiar to anyone who has used current large full-frame DSLR cameras.

The following photograph shows a Canon 5DsR (left) with the Canon 24-70mm f/2.8L II lens side-by-side with the Fujifilm GFX 50S with the Fujifilm 32-64mm f/4 zoom lens. (They have been positioned so that their backs roughly align with one another.)

The body widths and depths are rather similar, though. The lenses aren’t that different inside either, though the Fujifilm 32-64mm lens covers a smaller focal length range and has a smaller maximum aperture, and the Fujifilm lens diameter is larger than the Canon. I was surprised that the Fujifilm lens was not as heavy as I expected. Note that an optional Fujifilm adjustable viewfinder attachment is available but not included in this photograph.

Handling

In the hand, the GFX 50S felt much like holding and photographing with a full-frame DSLR. The weight, bulk, and balance of the 5DsR/lens combination and that of the GFX 50S felt roughly similar and rather familiar. Jeff and I both felt that the Canon’s body shape and curves were a bit more comfortable, and I noticed the narrower front “point” area of the Fujifilm grip, though this is something I would likely adapt to. Overall, our impressions of the handling of the GFX body were quite positive.

Viewfinder

The viewfinders are, obviously, quite different. The Canon has an optical viewfinder (OVF) while the mirrorless GFX 50S has an  video electronic viewfinder (EVF). Most users might have two questions about this. First, how does an EVF compare to the familiar OVF? Second, how good is the EVF by comparison to other cameras with this type of viewfinder?

The answer to the first question, comparing EVF and OVF viewfinders, involves some objective facts but ultimately leads to some subjective reactions. There is no delay in the OVF image, of course, and it has very high-resolution. Its familiarity makes it a sort of baseline for many photographers. On the other hand, there is always some latency (though it can be quite small) with EVF displays, and you are looking at a small monitor instead of “the real world.”

In my own prior experience with several EVF cameras, I found that I quickly adapted to EVFs and eventually wasn’t bothered by them. You may or may not feel the same, though I urge users to give them more than a brief look before making a final decision. EVFs provide some features that OVFs cannot provide, or at least not in the same way: they can provide exposure simulation to make the scene visible in very low light, magnification and other display aids help with manual focus accuracy, and a variety of data can be overlaid on the screen.

For those who generally work in “live view” mode (or its non-Canon equivalents) the EVF versus OVF question may almost be moot.

My answer to the second question — how does the GFX 50S display compare to other EVF displays — is somewhat subjective. I have used a variety of other Fujifilm EVF cameras, and the GFX display seemed at least as responsive to me. Jeff has experience with Sony mirrorless cameras and while he started out thinking that the GFX might be a bit slower, when he brought out an A7r for comparison, the two seemed pretty similar to both of us.

Menus and controls

There is a lot of subjectivity when it comes to how photographers respond to menu and control layouts on cameras, and opinions seem to vary based on what one is used to and how willing one is to adapt. Having used other Fujifilm cameras a lot, I was able to do almost everything I needed to do (format cards, change various settings, etc.) without reference to a manual.

I think that this point up another factor concerning menus and layout that is important. We tend to like what we are used to, and we find different interfaces to at least initially be disorienting. But we are adaptable, and with longer use an interface that initially seems  a bit awkward can become very intuitive. 

Summary

All in all, based on my afternoon with the camera, the interface and handling seemed just fine to me. My overall impressions were favorable, that the camera felt a lot like using a full size full-frame DSLR in most ways, and that it felt a lot smaller and more compact than traditional medium format cameras or other well-known miniMF cameras. It is a body that I would be comfortable using.

Another Model

At the time when I originally wrote this article, there was only one Fujifilm miniMF GFX camera, the 50S. As of November 2018 there is a second version, the 50R. The 50R is based on the same sensor (and, as is typical of Fujifilm systems, it shares most of the same electronic and image-making technology) in a smaller rangefinder-style body. Features that might make it an interesting alternative for some photographers include the smaller size, lighter weight, and lower price point.

Update June 2021: Since I wrote the previous paragraph a few years ago, Fujifilm has introduced other miniMF cameras. The first was a very large and expensive GFX 100 with a 100+MP sensor. Very recently Fujifilm announced a smaller and considerably less expensive camera with essentially the same sensor, the GFX 100s. And within the past week or so rumors of a replacement for the 50s have emerged — key features are a very low price near $4000, the inclusion of IBIS, and a smaller body much like that of the GFX 100s.

Image Quality

Most people don’t consider acquiring a camera like the GFX 50S for ergonomic reasons — they almost always cite image quality as the main appeal.  In fact, the potential for image quality improvement is what attracted me to miniMF and, specifically, to the GFX 50S. Most of this potential  is tied to the use of the larger sensor: high sensor resolution, low noise (on these modern miniMF sensors), good dynamic range, optimized system resolution, the perceived benefits of medium format and  miniMF lenses, differences in DOF and what some think is a “medium format look,” and so on.

When you consider that “look” issue, keep in mind that the miniMF sensors are as close to full frame in size as they are to the smallest of the many film MF formats, 645. Because of this the magnitude of any “medium format look” attributed to a larger sensor in comparison to full frame will be rather attenuated. The factors that might affect a 6×7 image area’s “look” are not nearly as present on the much smaller 33×44 digital sensor area.

(I’m not going to provide a detailed description of all of these issues here, though you can get some background from the other article I linked to above: Mini Medium Format… Or Not?)

A full objective analysis of these factors on one camera is a daunting task. Doing a dual analysis that allows a comparison of two different cameras is even more complex. A full comparison would use a variety of comparable lenses on the two systems, require careful camera positioning and focus and exposure adjustments to produce comparable results, test at a range of settings (focal lengths, apertures, ISO values, etc.), make decisions about how to account for different pixel dimensions of the two samples, and more — which was beyond what Jeff and I could or would attempt.

We had neither the time nor the inclination to dig that deep, so you’ll need to look elsewhere if that is the sort of thing you are trying to find. However, given the hope that the larger format can produce significant differences in photograph quality, these should show up even in a somewhat casual comparison  like ours.

(If you have looked at my linked article, you know that I’ve thought a lot about this, and that I had already come to some tentative conclusions and their meaning in the context of my own photography. Our experiments gave me an opportunity to challenge or verify some of my previous thinking… though the results are not absolutely conclusive.)

We did several sets of exposures on the two cameras, using a subject with a complex and detailed visual pattern of leaves. We tried two pairs of roughly comparable focal lengths (GFX 50S at 32mm and 64mm, 5DsR at close to 24mm and 50mm), a series of photographs at ISO values from 100-6400, and some at different apertures. Even this limited set of comparisons produced quite a few files!

I acknowledge that this test is not comprehensive and that it is doesn’t tell us much or anything about certain claims regarding the larges sensor — for example the effect of narrower DOF at a given aperture. 

Resolution at ‘normal’ focal length

Although the different aspect ratios of the two systems (3:2 on full-frame and 4:3 on miniMF) complicate comparisons a bit, we felt that comparing full-frame at 50mm (often described as a “normal” focal length) and miniMF at 64mm (giving a similar magnification) made sense. Before getting too deeply into the minutiae of comparing 100% crops, remember that both systems can produce excellent prints at quite large sizes — excellent 30″ x 40″ prints from either are a very realistic expectation.

A center resolution example

The first pair of images were shot at their respective “normal” focal lengths (about 50mm and 64mm), at ISO 100, and f/8. (In theory, the aperture choice would give a slight advantage to the miniMF system since it has a slightly smaller diffraction-limited aperture.) Exposures ended up being a partial stop different, which isn’t surprising when comparing two different cameras from two different brands.

Both cameras were on solid tripods, and the shutter release was by means of a 10-second self timer or an electronic release. The cameras were on separate tripods and positioned so that the lenses were perhaps a foot apart. Distance to the subject was virtually the same to within less than an inch.

So that you can play along, if you so choose, I present the two examples below without identifying which camera they came from. (You can cheat in various ways — including reading ahead! — but I think the comparison is more useful if you do it “blind” first.)

Neither has been sharpened or adjusted for brightness, color, etc. (Different systems often respond differently to color, but once you learn their “personalities” you can get equivalent color from them.) They were converted in ACR (Adobe Camera Raw), and then opened into Photoshop for cropping and saving as “10” quality .jpg files. The area shown is close to the center of both images.

Example 1

Example 2:

Aside from some color/exposure differences, what do you see? Can you see a resolution difference? How big is it? Which one do you think is the miniMF system and which is the full-frame system? Go ahead… take your time. ;-)

Before you answer, here are a couple more versions of the files. Anyone who works with raw files — that’s most serious photographers! — knows that so-called “straight out of camera” (SOOC) raw files, by their nature, do not look very sharp and will require additional processing in order to reveal the best qualities of the image. So, the following goes one step further, applying some basic sharpening processes to the two examples.

Example 1 sharpened:

Example 2 sharpened:

Answer below…

The first example was made with the Canon 5DsR and the second with the Fujifilm GFX 50S. Any difference in center resolution in this comparison is quite small  — and could be further reduced by applying sharpening settings optimized for each system’s files.

There’s more, but I’m going to take a break and leave the article at this point for now. I’ll be back to add more  data points later on…

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… and now I’m back with one more point of reference. (Update: January 19, 2018)

When it comes to resolution, making judgments based on screen images has its limits. For example, 100% magnification crops “show” you things that won’t be visible even in a very large print, and in many cases you must interpret what you see in the screen image in order to speculate about what the print will look like. As we say, “The proof is in the print.”

With that in mind, I have prepared some files that may be useful for comparing print resolution from Fujifilm GFX 50S and the Canon 5DsR. These files each hold three “test strips” labeled A, B, and C. The files have been formatted for producing prints with a print area of 10″ wide and 6″ tall (use letter-size paper) when printed at a resolution of 360. They are sRGB color jpg files in the highest quality (Photoshop: 12) jpg format.

There are four files. Let’s call them:

• Sample 1
• Sample 2
• Sample 3
• Sample 4

(Click on the links to see and download the files.)

Viewing them on screen is not the objective — in fact, for reasons I won’t go into here, trying to evaluate that way is of very limited value and may mislead you. (For example, the files have been optimized for print in ways that may make them look poor on screen at 100% magnification.)

You need to print the files.

Since there are four samples, you’ll need to make four letter-size prints. The correct settings will probably be entered automatically, but check that the print area is 10″ wide and 6″ tall and that the image resolution is set to 360.  (Set the printer resolution higher — a minimum of 1440 is recommended.)  As you download and print the files you may wish to make a note on each (in pencil or ink) indicating which file it is — “sample 1,” “sample 2,” “sample 3,” and “sample 4” for example.

Observe each print carefully. Note anything you can see related to the resolution of each printed strip A, B, and C. (Note that this is only a resolution test — don’t worry about things like image size, brightness, color, and so forth.)

In order to avoid confirmation bias I’m not going to reveal anything else about the files at this time. Once a few people (or a lot of people?) have weighed in with their observations — please use the comments below — I’ll reveal more important information about what you are looking at.

The following comes as an update on January 28, 2018.

Fujifilm GF 32-64mm f/4 R LM WR wide-angle lens

While considering the GFX 50S camera I can’t lose sight of the fact that lenses are important, too — and I had the chance to get a bit of an idea about the quality of the Fujifilm GF 32-64mm f/4 R LM WR wide-angle lens during this informal test. I have no illusions about the following report — this is not a formal lens test, and you should consider a sort of informal reaction to the opportunity to work with it briefly.

First, some initial impressions. Even to someone accustomed to working with large full frame DSLR lenses, the Fujifilm GF 32-64mm f/4 R LM WR wide-angle lens seems large, though perhaps not as much as you might expect. Because the mount for the GFX 50S camera is larger than that on full frame lenses, the diameter of this and other Fujifilm miniMF lenses seems quite large, especially for a lens with a maximum aperture of only f/4. Overall it feels like its weight and length are similar to that of my Canon 24-70mm f/2.8L II, although the Fujifilm’s zoom range is shorter and its maximum aperture is smaller. Photographers who have experience with traditional medium format gear, however, won’t find it to be unusually large — actually they will likely remark on its small size!

The lens is solidly constructed, as we would expect for a lens whose list price is well over $2000, and its operation is positive and smooth. It is not an image-stabilized lens, which isn’t too big of a deal as you are most likely to use this lens on a tripod-mounted camera. As is most often the case with Fujifilm lenses, it has an actual aperture ring, marked with apertures from f/4 to f/32 — and long-time photographers familiar with classic equipment are likely to appreciate this. The lens responds quickly and precisely to the zoom and manual focus rings. Many photographers accustomed to typical cropped sensor and full frame DSLR/mirrorless cameras will find that the 32-64mm focal length range seems small, but that isn’t unusual in lenses following the medium format traditions.

In keeping with my idea of offering “impressions” rather than a formal review of this lens, I’m not (currently, anyway) offering images that demonstrate the overall image quality, much less measured test results. (You can find these elsewhere online if you are interested.)

From my brief work with the 32-64mm lens I felt that its optical performance was first-rate. (Fujifilm’s metric is a claim that it is 100MP sensor ready, and I can’t disagree — but if you stop and think about this claim, you may discover that it means less than you think*) Image resolution is excellent across the frame, all the way into the corners, and at a wide range of apertures including the largest at f/4. I did not notice any meaningful vignetting with the lens, either. (By comparison, my Canon 24-70mm f/2.8, which I regard as a fine lens, can become a bit softer in the far corners at the largest aperture and it also vignettes more — not typically in a visibly way, but in a photograph with smooth gradients you may be able to see it, and you might choose to compensate in post.)

One important caveat: Apparently Fujifilm optimizes the images automatically in the camera, and those optimizations are baked into the raw files. So when you look at SOOC (“straight out of camera”) Fujifilm files, they have already been optimized in ways that you might apply manually during raw conversion to images from other lenses. In other words, a Fujiflm SOOC file is not the same thing as a Canon SOOC file.

A zoom lens like this one has more versatility than a prime, though it also has the downsides of larger size and weight along with a smaller maximum aperture. I could see an important role for this lens in my landscape photography. I prefer zoom lenses for such work (for a variety of reasons that I won’t detail here), and this Fujifilm lens provides the extra functionality while maintaining excellent image quality.

*  About that Fujifilm claim that their miniMF lenses are “ready for 100MP” sensors… That sounds quite impressive, doesn’t it! It certainly will be important to those who may eventually use Fujifilm 100MP miniMF cameras. But if you do a bit of simple math you’ll see that it is an entirely predictable capability.  In round numbers (but very close!) one 100MP miniMF 33×44 sensor has about the same area as four 1.5X APS-C sensors of the sort used in Fujifilm’s 24MP and 26MP APS-C cameras — which means that they have virtually the same pixel pitch as the 100MP sensor has. The lenses on those cameras are already capable of sufficient resolution for these cameras… and a 100MP miniMF sensor places no greater stress on the lenses. To be honest, this actually suggests that their Fujifilm lenses should be capable already or supporting even higher resolutions.

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Products mentioned in the article:

• Canon 5DsR DSLR camera
• Canon EF 24-70mm f/2.8L II lens
• Fujifilm GFX 50S camera
• Fujifilm GF 32-64mm f/4 R LM WR wide-angle lens
• Pentax 645z and 645d

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G Dan Mitchell is a California photographer and visual opportunist. His book, “California’s Fall Color: A Photographer’s Guide to Autumn in the Sierra” is available from Heyday Books and Amazon.
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