Our latest test scene simulates both daylight and low-light shooting. Pressing the 'lighting' buttons at the top of the widget switches between the two. The daylight scene is manually white balanced to give neutral grays, but the camera is left in its Auto setting for the low-light tests. Raw files are manually corrected. We offer three different viewing sizes: 'Full', 'Print', and 'Comp', with the latter two offering 'normalized' comparisons by using matched viewing sizes. The 'Comp' option chooses the largest-available resolution common to the cameras being compared.

The GFX 50S's resolution capture is, as you might expect, impressive. That said, the Canon EOS 5D SR, shot with the relatively lowly 85mm F1.8 lens is able to do a similar job. All four cameras, with good prime lenses on are exhibiting moiré in the finest detail in the scene.

In terms of high ISO noise, the GFX 50S performs fairly similarly to the Pentax 645Z and, as sensor size alone would lead you to expect: better than the Canon EOS 5DS R. However, because Sony's a7R II sensor uses a more modern BSI design, it's able to be more efficient, which means it's able to close the gap to the bigger sensor cameras.

The GFX 50S's JPEGs are every bit as pleasant as they are in the company's smaller cameras. Color response is bright and punchy, with both skies and skintones well represented. And, of course, the Film Simulation modes mean there are a selection of good-looking options available. Default sharpening is quite strong but is effective at emphasizing fine detail in the scene: taking the level of apparent detail ahead of its rivals, without adding too much in the way of haloing at high contrast edges.

Similarly, noise reduction does a good job of balancing the retention of detail with the suppression of noise. We're not sure many people are looking to buy a medium format camera to shoot JPEG but they're very usable even at the camera's highest setting. Which just makes it seem more peculiar that Fujifilm limits the camera to a relatively modest ISO 12,800.

Dynamic Range

Looking at our ISO Invariance tests, we can see that an image shot at ISO 100 and pushed six stops looks noisier than one with the same exposure, shot at ISO 6400. This shows that the sensor is still contributing a little noise to its images (enough that you'll see it, if you multiply it 64 times!). However, the 5EV push of an ISO 200 shot looks a lot like the ISO 6400 image, which suggests it's a very good sensor.

However, the exposure latitude test, where we lift the shadows in images shot at progressively lower exposures shows that its performance is only slightly better than that of the D810, despite receiving more total light (double the exposure time and half the light per square cm, captured on a sensor with more square cm of area). Now consider the fact that the D810 has an ISO 64 mode, which would allow you to use a 2/3EV brighter exposure before the sensor clips. We expect this will give a real-world result similar to when we pitted the Pentax 645Z against the Nikon.

Recoverable highlights

ISO 6400 | 1/250 sec | F4 |

The above scene is a tricky one to properly expose. The photographer should have exposed for the highlights, and pushed the shadows in post.
Thankfully, above ISO 1600, the GFX 50S applies no additionally amplification, retaining highlight info. The above image was processed in Adobe Camera RAW. Using the Exposure and Highlights slider, the background was recovered.

Dynamic range is measured from the point at which the camera clips to white (above which there is no usable data), down to the noise floor at which you think the signal-to-noise ratio is unacceptable (note the subjectivity of that limit). Generally speaking, there shouldn’t be such a thing as ‘recoverable highlights’ because once a sensor has clipped, it’s unable to capture any difference in signal. There’s a little margin for error because one channel may clip before the other two, which leaves a little scope for clever algorithms to try to guess an appropriate value for the clipped channel, which leaves the degree of highlight recovery highly dependent on which channel has clipped and what color you’re trying to recover. Significant amount of highlight recovery usually mean that your JPEG is failing to make good use of all the captured data: it’s a failing of the JPEG engine, rather than a strength of the sensor.

However, there are situations in which the GFX 50S will have considerable amount of recoverable highlights, thanks to the way it shoots at high ISO. Above ISO 1600, the camera stops applying any additional amplification and instead leaves a metadata tag telling the Raw converter to brighten the image by between 1 and 5 stops (to generate its ISO 3200 to 51,200 modes). This approach means that, for an ISO 3200 exposure, you’re recording your captured data one stop further down in the Raw file, meaning an additional stop of highlight data is recorded that would have been pushed to clipping, had amplification been used. Your Raw conversion software will probably initially clip this extra data (by applying the default ISO 3200 tone curve), but for these higher ISO settings, you should find a stop of accurately recoverable highlight information for each stop you lift above ISO 1600.

Moiré

ISO 100 | 1/60 sec | F11 | 120mm
The amount of detail in the above image is pretty impressive..

...but moiré is noticeable in fine detail, as shown in the 100% crop above.

Fujifilm's X-Trans filter array is effective at mitigating moiré without the need for a low pass filter. However the GFX 50S doesn't use X-Trans (it uses a Bayer filter array) and has no low pass filter. As a result, and as shown in the studio test scene, moiré can be a problem in very fine detail. We noticed it mainly in city shots, like the one above, and in the fine detail of garments, like in the image below.

There's been a trend towards removing AA filters from Bayer sensors once their pixel count it high enough. In these instances, they appear to be trusting the lens or diffraction to have an anti-aliasing effect. This is generally done when you exceed 200 pixels per mm. This sensor in the GFX 50S is 187 pixels per mm.

ISO 5000 | 1/200 sec | F2.8 | 63mm
Moiré is very noticeable in Richard's suit (purple and green areas).
Photo by Erin Carey

Color Chrome Effect

For a professional camera, the GFX 50S makes an unusual amount of effort to deliver a near-final image, out-of-camera. Color Chrome Effect is probably the clearest example of this. The company says it’s an attempt to mimic the response of its ‘Fortia’ filmstock. The idea is to boost contrast in saturated areas of the photo, to prevent the image looking flat for high saturation subjects. The effect can be applied in two levels (weak and strong) and can be applied as you shoot or in post-shot in-camera Raw processing. The effect requires considerable processing muscle, so can’t be used in continuous shooting mode.

Color Chrome Off Color Chrome Weak Color Chrome Strong

We were impressed with the results: the camera is able to selectively darken highly-saturated colors, so that contrast is boosted, giving real punch to the images (and helps rescue prevent much of the red clipping to magenta in this example). And, since it’s available through the camera’s in-camera Raw reprocessing feature, there’s the option to output TIFF images if the camera’s processing can get you closer to a final image than your available time or Raw processing skills allow.