DR vs. Full well

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dts350z
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Joined: Fri May 18, 2018 6:00 am

DR vs. Full well

#1

Post by dts350z »

How is DR (stops) calculated, compared to Full Well?
ASI1600 Plot.png
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I'm curious about the region between zero gain and 60. The full well doubles but the DR is flat?

Is that because all the e- values produce the same ADU due to the 12bit DAC? If so, how can you measure the full well?
dts350z
Posts: 39
Joined: Fri May 18, 2018 6:00 am

Re: DR vs. Full well

#2

Post by dts350z »

OK I understand now.

DR (stops) - log2(full well/read noise)

Except you can't go above 12 because the ADC is limited to 12 bits.

The "Full Well" goes down as the gain goes up because you run out of head room at the input to the ADC. So it's not really "Full Well" but rather the max number of e- that will produce the max digital ADC output.
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Re: DR vs. Full well

#3

Post by admin »

Yep, that's exactly correct.

Full well is the common term for the measurement (and accurate at minimum gain), but at higher gains it is really something like 'saturation electron count'.

cheers,

Robin
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