Listening to Victor Ha from FUJIFILM in our interview recorded here, there was one thing talked about that actually struck me – there may be this new sensor and picture processor within the X-H2S that permits studying the sensor knowledge at 14-bit for as much as 30 frames per second. A brand new F-Log2 profile is added to accommodate the brand new sensor capabilities. This can be a distinctive function for a client digicam that might actually permit a lot greater dynamic vary values. Therefore, I used to be fairly curious to run the brand new FUJIFILM X-H2S by way of our lab check procedures. Curious too? Then learn on…
Thus far, all the buyer digicam sensors that I’m conscious of permit the upper body price recordings required for shifting pictures solely at 12 bit sensor readout modes. 14 bit sensor readout modes have been reserved for high-end cinema cameras just like the ARRI ALEXA, for instance. Now, FUJIFILM brings this function right into a client hybrid stills / video digicam, the X-H2S. Plus, inside 10 bit 4:2:2 ProRes HQ recording. Wow.
And, FUJIFILM declare as much as 4x greater sensor readout speeds. Time to torture check this new digicam in our lab!
Utilizing our strobe mild, which creates the sequence of black and white bars (associated to the readout nature of CMOS sensors), we’re getting the primary lead to UHD 25 frames per second: 9.7ms (much less is best).
This can be a good outcome, contemplating the 14-bit readout of the sensor! For 3:2 6.2K open gate mode, we’re getting 11.5ms. Fairly apparently, and in step with FUJIFILM’s statements that for greater frames per second the sensor readout mode adjustments to 12bit, we’re getting 5.3ms at UHD 60fps. In UHD 120fps, the readout mode adjustments once more, a slight crop is utilized (1.29x) and we get 3.9ms.
Now it will get attention-grabbing. If you’re not conscious of how we check the dynamic vary, please take a look here.
Let me shortly summarize why we’ve 3 methods to guage the dynamic vary of a digicam:
- The waveform plot of the Xyla 21 chart at native sensor decision on a timeline with that decision: this offers a visible indication of what number of stops will be recognized above the noise ground. Additionally, it reveals the code worth distribution of the stops. Fairly often, the decrease stops are very shut collectively by way of code worth, therefore if you happen to underexpose and lift the shadows later in submit (i.e. increasing the shadow stops), you’ll not have sufficient code values between the stops and the result’s ugly banding (lack of nice coloration transitions between the stops).
- IMATEST: IMATEST will calculate the sign to noise ratio for every cease. That may be a purely mathematical calculation and turns out to be useful to determine, how “clear” every of the stops is. Cameras that use lots of inside noise discount naturally fare higher than others with much less noise discount. There isn’t any solution to account for that in a significant approach, because the noise footprint of each digicam / sensor is totally different. Therefore, there may be additionally no “customary” noise discount which you can apply in submit to check cameras. That’s why we at CineD all the time flip off the noise discount – as advisable by IMATEST.
- Latitude: publicity latitude is the potential of a digicam to retain colours and element when over- or underexposed. Our CineD studio scene is the true world check (in a managed surroundings) of how far a digicam will be pushed. The fantastic thing about this check is that it clearly reveals what number of stops are usable in our rigorously composed customary scene, because the playfield will get equalized – and, it’s revealed if a digicam is “dishonest” through the use of extreme inside noise discount. Simply to say it: another actual world scene with a special distribution of lights and shadows would present a special outcome. Regardless of how a lot inside / or submit noise discount is used, cameras that present a stable 12 stops at a signal-to-noise ratio of two usually have 8 stops of latitude in our scene. Cameras, just like the ARRI ALEXA, that present 2 stops extra at SNR = 2 even have two stops extra latitude. Cameras that attempt to obtain one thing near 12 stops at SNR = 2 through the use of heavy inside noise discount solely present 7 stops of latitude.
So, this trinity of checks could be very revealing and helps to determine if the mix of sensor readout, sign processing, and codec permits to push publicity round over a wide range.
FUJIFILM X-H2S at ISO1250:
Utilizing ProRes HQ, the brand new F-Log2 profile with a local ISO of 1250 and the native sensor decision of 6240×4160 open gate 3:2 mode, turning “noise discount” to -4 and interframe NR “OFF”, we get the next waveform plot:
13 stops will be recognized above the noise ground. The noise ground appears relatively clear, which hints at further in-camera noise discount although we tried to show it down so far as attainable.
There’s a stable code worth distinction between the eleventh and twelfth cease, in addition to from the twelfth to the thirteenth cease in F-Log2. This implies: if you happen to underexpose your photographs and you have to push up these decrease stops (and successfully broaden them), you’re much less more likely to run in to issues like banding and lack of coloration transitions.
IMATEST calculates the next:
IMATEST reveals 11.9 stops at a signal-to-noise ratio (SNR) of two and 13.4 stops at SNR = 1 (on a 6.2K timeline). That may be a superb outcome for a client APS-C sensor (The ARRI ALEXA traditional confirmed 13.8 at SNR = 2 and 14.8 at SNR =1, to present you our present benchmark)!
Additionally, if you happen to take a look at the center graph above the blue “13.4” line, there are nonetheless about 2 extra stops recognized. That’s truly a bit higher than the BMPCC 6K, not a lot for SNR = 2, however the SNR = 1 worth is half a cease higher (additionally measured in 6K, check here). In comparison with that, the Canon C70 (lab check here) trumps each with 12.8 stops at SNR = 2 and 14.2 stops at SNR = 1 for XF-AVC Intra C-Log2 (12.3 at SNR = 2 and 14 at SNR = 1 for CRAW).
Simply to present you this extra knowledge level: scaled to 3840×2160 UHD, I get 12.2 stops at SNR = 2 and 13.6 stops at SNR = 1.
As described earlier, latitude is the potential of a digicam to retain colours and particulars when over / underexposed and pushed again to a base reference degree.
For our CineD studio checks, the bottom publicity degree refers to a waveform worth of round 60% on the brow of my pricey colleague Johnnie. The digicam was once more in 6.2K ProRes HQ F-Log2 open gate mode at ISO1250 (noise discount at -4 and interframe NR “OFF”):
For base publicity, we uncovered a bit under 60% to permit for 4 stops of overexposure with out clipping the pink channel on Johnnie’s brow, then introduced again to base publicity:
Now, let’s successively underexpose the scene by closing the iris of the lens to T8.0, after which halfen the shutter worth.
At 3 stops below base publicity, pushed-back noise begins to kick in:
The noise could be very nice, very natural wanting. No want for noise discount, in my view. Bear in mind, we’re already at 7 stops of publicity latitude. Different cameras survive this level solely by making use of noise discount in submit.
The 4 stops underexposed, pushed again picture appears like this:
Noise is now very dominant inside the picture, however nonetheless very nice, natural wanting. We’re at 8 stops of publicity latitude! Noise discount in DaVinci Resolve simply removes any extreme noise:
We’re already at 8 stops of publicity latitude. Now, the massive query is, can we push it one cease extra, to 9 stops of publicity latitude?
Let’s take a look:
Heavy chroma and luma noise is now current within the picture, not so nice any extra. When utilizing noise discount in DaVinci Resolve, we get this:
This nonetheless appears surprisingly good, truly! Nonetheless, the background coloration modified to gray as an alternative of olive, and the shadow aspect of Johnnie’s face is rendered pinkish as an alternative of orange – which I don’t like. However, there are not any giant blotches of chroma noise or horizontal or vertical traces. Even the shifting picture nonetheless appears fairly okay.
Decide for your self, however that is near acceptable, and we’re at 9 stops of publicity latitude. Please take a look at different cameras just like the Canon C70 (check here), full-frame cameras just like the Sony A1 (check here), or the current Sony VENICE 2 (check here) – the FUJIFILM X-H2S undoubtedly trumps the C70 and even the Sony A1, whereas the 5 stops underexposed picture appears nearly pretty much as good as with the VENICE 2 in 4K ProRes HQ – and we’re speaking a couple of full-size cinema digicam right here.
If we evaluate the 5 stops underexposed picture with the chief of the pack, the ARRI ALEXA Mini LF (lab check here) it turns into clear, nevertheless, that it can not compete – the 5 stops below picture of the Mini LF undoubtedly appears significantly better, truly even the 6 stops underexposed picture does. And, the Mini LF has one cease extra within the highlights as nicely, resulting in 10 stops of publicity latitude.
So, a stable 8 stops with further wiggle room in the direction of 9 stops – that’s fairly spectacular and is definitely higher than a lot of the current full body client cameras. Good job, FUJIFILM!
The FUJIFILM X-H2S fares very well for a client digicam in our lab check, particularly when contemplating that it’s an APS-C digicam, not full body. The rolling shutter efficiency is superb, the dynamic vary outcomes are spectacular, as is the latitude check. It turns into clear from these outcomes that the 14-bit sensor readout undoubtedly is a part of this good efficiency.
So, you may truly say it’s a BMPCC 6K on steroids with a ton of further options like IBIS and all the different benefits of a real hybrid digicam, together with a smaller type issue.
Have you ever used the FUJIFILM X-H2S but? Please tell us what you assume within the feedback under