Many thanks for taking the time to measure all this, its indeed very interesting.
About row noise please check the application note from CMOSIS I emailed you (a1ex), they suggest applying a reference voltage to some additional sensor pins and report a significant improvement in row noise behavior.
About PLR:I also think it can go beyond the officially listed 15 f-stops - I ran tests with +6 F-stops and while the footage was not without flaws in general it worked and definitely looked promising.
I noticed though that color saturation decreases with the amount of PLR highlight recovery and the fixed pattern noise is getting stronger in those areas. Both effects might be possible to compensate in internal image processing. Maybe we can measure/benchmark those settings as well in the future.
Here is a quick +6 stops test where I varied the lens aperture to measure latitude differences before turning on PLR:
PLR HDR vs HDRx:As I understand it (I have not personally shot any HDRx footage on Red cameras) the differences are:
-) HDRx saves 2 exposure bracketed image streams and you can mix them together with different algorithms in post.
-) PLR HDR combines 2/3 (selectable) exposure brackets and mixes them together based on luminosity threshold on the sensor as the images are gathered already. The output is a single image stream - no post processing required to combine exposures.
-) with PLR highlights loose light sensitivity - shadows keep their light sensitivity - the curve can be tweaked in all aspects.
-) with PLR flickering can occur in highlights created by flickering light (AC tungsten, flickering CRT screens, magnetic ballast fluorescent tubes) as PLR reduces exposure time in highlights, but PLR actually does up to 3 exposure phases in one normal exposure time (not a single short one) so the effect might not be that visible -> will require more tests (I have not seen flickering in any PLR footage I shot yet - but I used PLR tweaking mostly with bright sunlight which will obviously not start to flicker
)
About max FPSThe CMV12000 V2 can indeed go up to 300 FPS at full 4096x3072 resolution in 10 bit mode, in 12 bit mode this max FPS is reduced to 180 FPS according to official specs. By reducing the number of read rows (smaller window -> e.g. reading a 16x9 window from the 4:3 sensor) the max FPS will increase beyond the 300/180 FPS.
Other SensorsCanon doesn't sell their sensors, Sony only sells to partners or large volume orders and they only sell a small selection of the sensors, not their latest cinema ones. There are only a few companies who sell large diameter sensors beside the mentioned Kodak/Truesense, Cmosis, Aptina that are OnSemi (VITA12/16/25 series) and dynamax imaging which all offer similar specs for similar prices.
The biggest factor for us though is that the sensor datasheet can be shared without an NDA and that only Cmosis and Truesense agreed to. It is essential that developers and the community have access to this documentation and we will not incorporate any image sensor that has no open documentation. After all these measurements as a1ex did them would have been pretty much impossible otherwise.
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