Re: [APML] Dynamic Range of CCD

[Jerry Lodriguss <jml@astropix.com>]

>Here is the math:
>
>k = 20log10(S/N) dB ----- eqn(1)
>S = largest signal strength
>N = smallest signal strength (or noise)
>In the KAF3200 datasheet, k = 72-77dB
>
>Let decompose eqn(1): We get
>S/N = 10^(k/20) and we plug k = 72, 77 into this.
>
>For k = 72, then S/N = 10^(3.6) = 3981
>For k = 77, then S/N = 10^(3.85) = 7079
>
>To convert to number of bits:
>
>For k = 72, S/N = 3981, bits = log(3981)/log(2) = 11.96 bits
>For k = 77, S/N = 7079, bits = log(7079)/log(2) = 12.79 bits
>
>So my original of 12 - 12.8 bits is very accurate. Bottom line is the
>dynamic range ranges from 3981 - 7079 as the ratio from the brightest to
>the faintest. Hope this help, and hope I did not mess the math up <g>.



Hi Loke,

Thanks, I have faith in your math but not in mine! The question is, did *I* 
mess the math up.<G>

Is that about 13 to 14 F/stops then?


Jerry
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