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Old 05-12-2019, 11:05 PM
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The_bluester (Paul)
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Join Date: Feb 2011
Location: Kilmore, Australia
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that more or less covers what I reckon the limitation is. The IMX294 sensor is advertised as having approx 64ke pixel Wells, but the ADC on the camera is 14 bit, so anything above approx 16k count on the sensor will max the conversion at unity gain. I have found results to generally be better at unity gain than at lowest gainwith better faint detail, but brighter stars blow out.

It more or less comes down to good discrimination of levels with reduced effective dynamic versus a high apparent dynamic range but an effective loss of QE. Does it matter in the end if it takes say one versus four photons to produce an electron for 100 versus 25% QE, or 100% QE (Perfect world example) and one versus four electrons per ADC count? It still equates to a significant loss of discrimination regards to captured light versus data.

Your KAF 8300 example is a good one. The ADC can faithfully represent the entire dynamic range of the sensor as the ADC range is greater. Many (most?) of the current CMOS cams are the other way around with the ADC having a smaller range than the sensor.
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