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Old 09-12-2019, 08:36 AM
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The_bluester (Paul)
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Join Date: Feb 2011
Location: Kilmore, Australia
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Without seeing specs on the next generation of sensors it is hard to draw too many conclusions for anything but the IMX294 based cameras or others which may have some form of dual gain mode that creates a big drop in read noise. I have no idea whatsoever what the difference is at gain 120 that cuts the noise from approx 8 to approx 2 electrons but per my posts above, the difference in images shot is very noticeable and I will take it gladly.

As I have said previously, you can't and I don't blame Sony for putting in a 14 bit converter as the sensor is designed for a different application. It is hard to see a security camera needing to provide a faithful reproduction of a scene where real world sensor levels you want to capture and quantise can literally span the range of two to 65K electrons in a single exposure of 300 seconds or more, just that it would be a great party trick for an astro cam to be able to do. The party trick of this sensor as a security cam is concurrent dual length exposures for HDR output. The RGGB pixel arrangement is actually RRRR-GGGG-GGGG-BBBB as each pixel is a block of four sub pixels of the same colour which can be exposed for different times in one shot.

Another interesting but significantly pointless point. There does not seem to be any such thing as "Unity" gain. That is supposed to be 117 by the literature and my understanding is the high gain conversion mode starts at 120, but gain 120 is 1.000something electrons per ADU count (I would have to look up the exact figure from a .fit file) which is still marginally below unity in my book, presumably the official unity gain of 117 is lower still.
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