What's new and how it compares
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The GFX 100 builds on what the GFX 50 models have started, but add features that significantly broaden what you can expect from a medium format camera.
Key takeaways:
- Large, high-resolution sensor with latest technologies to maximize both low ISO dynamic range as well as high ISO performance
- In-body image stabilization to extend the circumstances in which you can get the full benefit of 100MP of resolution
- On-sensor phase detection speeds up the camera's autofocus considerably
- 4K video capability
New sensor
The most striking new feature of the GFX 100 is its move to using a 100MP sensor: way beyond the resolution of anything we've previously seen on a sub-$10,000 camera. It's important enough to be included in the camera's name and, unsurprisingly, a lot of the camera's other new features are focused on getting the most out of this sensor.
As with the rest of the GF system, the GFX 100 uses a 44 x 33mm medium format sensor. This is the smaller of the two current digital medium format sizes, but is still around 70% larger than 'full-frame,' so rightly earns its title.
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| 44 x 33mm wouldn't be considered especially large for a piece of film, but it's the second-largest digital sensor format made in appreciable quantities, so earns its 'medium format' billing. |
Digging a little deeper, it's a backside-illuminated design, which maximizes the region of each pixel that's light-sensitive, but also pushes the light-sensitive area closer to the top of the sensor. This can improve performance at the corners of the chip, where light can be arriving at very shallow angles.
Most significantly, the chip uses a dual gain design. This has pixels with two modes, switching to a higher level of in-pixel gain at high ISOs, reducing the noise level in low light images, at the cost of a slight reduction in dynamic range. In many respects, the GFX 100's chip resembles four X-T3 sensors placed next to one another, which is likely to mean it's similarly up-to-date in terms of its design and, we'd expect, its performance.
16-bit is unlikely to make a significant difference in the real world
The sensor in the GFX 100 is also one of the first we've seen able to output 16-bit files. This is unlikely to make a significant difference in the real world and our early investigations support this. Raw files are linear, so devote most of their values to the brightest tones. But, counter intuitively, the brightest tones are the ones with the highest magnitude noise, so you risk encoding that noisy data with more precision than necessary. You might gain an increase in performance in the very deepest shadows, but only if the sensor has low-enough read noise that it is still producing meaningful data to store there.
Image stabilization
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| Despite its large sensor, Fujifilm has managed to create an IS mechanism that can stabilize it |
The GFX 100 is the world's first medium format camera to offer in-body image stabilization. The five-axis system is rated at 5.5 stops of correction, when tested to CIPA standards. The tests were conducted with the 50mm equiv. GF 63mm lens, so we'd expect the number to be a little lower at longer focal lengths.
Image stabilization should probably also been seen as a way of maximizing the amount of detail you can get
However, as much as extending the range of shutter speeds that can be used handheld, image stabilization on a 100 Megapixel sensor should probably also been seen as a way of maximizing the amount of detail you can get at every shutter speed. The higher resolving power of the 100MP sensor means you'll see the effect of shake more readily (or, at least, lose the full benefit of the sensor's resolution sooner), so image stabilization is, perhaps, a required technology if you're going to see the benefit of that pixel count without using a tripod.
Anti-shock shutter mechanism
In addition to the image stabilization system, Fujifilm has mounted the camera's shutter mechanism so that it's isolated from the camera's body as well as the sensor, helping to minimize the risk of vibration affecting the images.
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As you'd expect, there's also a choice of fully mechanical, fully electronic or electronic first curtain shutter. Probably the most flexible mode is 'Electronic First Curtain + Electronic shutter'. This uses electronic first curtain mode to minimize vibration during long and moderately long exposures, then switches to fully mechanical shutter mode between 1/1250 and 1/4000 seconds, where EFCS could damage bokeh rendering, then moves to fully electronic mode to extend the shutter speed range beyond the 1/4000 sec limit of the mechanical mechanism.
The full electronic shutter option allows completely silent operation, but at around 159ms (~1/6 sec) is still slow enough to risk significant rolling shutter distortion in your images. 16-bit mode is around half this speed again, so is likely to show subject distortion with almost any moving subject.
On-sensor phase-detection
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The GFX 100 is the first medium format camera to offer on-sensor phase detection. This is a technology pioneered by Fujifilm (and first used in its compacts), which gives the camera information about how far away the subject is, so that it's able to drive the lens to the correct position, rather than having to constantly check for highest contrast as the lens refocuses.
The GFX 100 then conducts a fast contrast-detection confirmation, so that it can improve on the speed of the GFX 50 cameras without sacrificing precision. As with the early X-series lenses, it's likely that the large focus elements in the GF-series lenses will stop the GFX 100 keeping up with the best sport-optimized lenses of its mirrorless rivals, but it should mean faster, more decisive results in good light and reduce the camera's need to re-check focus (which is especially valuable in low light, where focus 'hunting' takes longer).
Fujifilm suggests as much as a doubling of AF speed.
Improved video capabilities
The GFX 100 is not only the first image stabilized medium format camera, it's also the first to shoot 4K video. And it can do so in 10-bit color, captured internally, a spec only matched by handful of cameras outside the dedicated video sphere. This allows the capture of greater dynamic range or produces more flexible Log footage.
The camera is clearly line-skipping to achieve this, so is likely to be more moiré-prone than, for instance, Fujifilm's own X-T3, which reads all its pixels and then downsizes the results. But it also means that the GFX 100's video isn't rendered unusable by the rolling shutter the camera exhibits in electronic shutter mode.
Our initial impressions are that its rolling shutter is around 28ms (1/36 sec) in 4K mode, which is a reasonable performance. For reference, the Panasonic GH5S's ~12ms rate would be considered very good, while the Canon EOS 5D IV's rate of ~31ms is likely to be problematic for some subjects and situations.
High-res viewfinder
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Like the GFX 50S, the GFX 100 features a removable EVF module. The module that comes with the GFX 100 is higher resolution than the one in the 50S, with an impressive 5.76M-dots. This means it's almost certainly the same 1600 x 1200 pixel display used in Panasonic's S1 and S1R, but using the full 4:3 region.
The lower-resolution finder from the 50S will function on the 100, but you won't get the full high-res experience that the camera can offer. The new finder is fully compatible with the optional multi-angle EVF-TL1 adapter that can be fitted between the camera body and the finder module to allow tilt and rotation.
Features
Bracketing
The GFX 100 gains a selection of bracketing options. In addition to exposure bracketing, the 100 offers Film Simulation and focus bracketing.
Exposure bracketing offers an extensive range of options, allowing up to ±9 shots, with steps of between 1/3 and 3 stops in 1/3-stop increments. There's a choice of whether each shot needs to be triggered individually or if they're shot continuously. Focus bracketing can shoot up to 999 images, with variable step sizes (indicated as 1-10) and the option to add an interval between each shot.
Smooth Skin Effect (and real-time Color Chrome Effect)
The GFX 100 adds a 'Smooth Skin Effect' processing option. This may sound like an odd feature to add to such an overtly pro-targeted camera but, given how good the JPEGs from the GFX line have been up to now, we think it makes sense to provide these fine-tuning options. The effect is extremely subtle (only really apparent in side-by-side comparison), but it gives a slightly more forgiving approach to skin texture than 100MP and the super-sharp GF lenses might otherwise do.
Like the previous GF cameras, the GFX 100 offers the Color Chrome Effect option that selectively darkens highly saturated colors to present a more compelling representation of certain subjects (such as flowers). The GFX 100's more powerful processor allows it to apply Color Chrome Effect in real time, rather than slowing the camera down.
Both these effects can be retroactively applied using in-camera Raw conversion.
How it compares
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Whereas the GFX 50 cameras struggled to put blue water between themselves and the best of their full-frame peers, the GFX 100's impressive range of features helps it stand apart from its rivals.
| Fujifilm GFX 100 | Fujifilm GFX 50R |
Hasselblad X1D | Phase One IQ4 150 | Panasonic DC-S1R | |
|---|---|---|---|---|---|
| Camera type | Mirrorless | Mirrorless | Mirrorless | DSLR | Mirrorless |
| Sensor size | 43.8 × 32.9mm | 43.8 x 32.9mm | 43.8 x 32.9mm | 53.4 x 40mm | 35.9 x 24.0mm |
| Image stabilization | In-body | Lens Only | None | None | In-body |
| Pixel count | 102MP | 51.4MP | 50MP | 150MP | 47.3MP |
| Max resolution | 11648 × 8736px | 8256 x 6192px | 8272 x 6200px | 14204 x10652px | 16736 x 11168px* 8368 x 5584px |
| Min ISO | ISO 100 (expand 50) |
ISO 100 (expand 50) |
ISO 100 | ISO 50 | ISO 100 (expand 50) |
| Max ISO | ISO 12,800 (expand 102,400) |
ISO 12,800 (expand 102,400) |
ISO 25,600 | ISO 25,600 | ISO 25,600 (expand 51,200) |
| Card slots |
2 x SD (UHS-II) |
2 x SD (UHS-II) | 2 x SD | XQD, SD | XQD, SD |
| Max frame rate | 5 fps (14-bit) |
3 fps | 2.3 fps | 0.7 fps (16-bit) 1.4 (14-bit) |
9fps |
| Autofocus system | On-sensor phase detection | Contrast Detect | Contrast Detect | Secondary-sensor phase detection | Contrast Detect (with DFD) |
| Battery life | 800 | 400 | <250 (estimate) | Unknown | 360 |
| LCD | 3.2" 2.36M-dot 2-way tilting | 3.2" 2.36M-dot tilting | 3" 920K-dot | 3.2" | 3.2" 2.1M-dot 2-way tilting |
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Touch-sensitive? |
Yes | Yes | Yes | Yes | Yes |
| Viewfinder | 5.76M-dot 0.86x mag |
3.69M-dot 0.77x mag |
2.3M-dot | Optical | 5.76M-dot 0.78x mag |
| Video spec | 4K/30p | 1080/30p | 1080/25p | N/A | 4K/60p |
| Dimensions | 156 x 164 x 103mm | 161 x 97 x 66mm | 150 x 98 x 71mm | Unknown | 149 x 110 x 97 mm |
| Weight | 1,400g | 775g | 725 g | Unknown | 1,020g |
| Price (body only, MSRP) | $10,000 | $4500 | $8600 | ~$55,000** | $3700 |
The GFX 100 doesn't have any direct peers. It's significantly less expensive than the 54 x 40mm medium format cameras but adds on-sensor phase detection and image stabilization, along with 4K capabilities and decent battery life.
The alternative, of course, is a full-frame camera, such as the Panasonic S1R, which uses a multi-shot mode in an attempt to exceed the GFX's resolution. However, while this multi-image approach boosts the image quality (in terms of DR and noise, as well as resolution), it also significantly limits the range of subjects it can be used for, which has the odd effect of making the Fujifilm look like a high-res all-rounder.
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