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Hi,
I find it very confusing how they measure the dynamic range. They compare a low ISO, say 200 where they reach the full well capacity and compare that with a high ISO, say 3200 where the readout nosie is at lowest.
Is this interesting to know?
When working in low nosie mode at ISO 3200 you have a very low roof.
If the gain at ISO 3200 is 4 (unitygain at ISO 800), and the Full Well capacity is 50000e-, then you just use the first electrones 0 to 4000 (14-bit ADC). The electrones from 4000 to 50000 you just trash away. With a 16-bit ADC you use the electrones 0 to 16000 with the gain 4. But normally there is much more complicated to construct a low noise 16-bit ADC if it shall be fast which are one of the demands in a DSLR.
If you have very low readoutnoise you can do a lot of short time exposures and get high dynamic, but the DSLR cameras mechanical shutter wont last for long.
/Lars
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