Archived posting to the Leica Users Group, 1999/10/14

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Subject: Re: [Leica] Re: Leica Users digest V12 #68
From: Mark Rabiner <mrabiner@concentric.net>
Date: Thu, 14 Oct 1999 16:47:56 -0700

Alexey Merz wrote:
> 
> Alexey Merz:
> >>Nope. The electon signal accumulated in the CCD potential
> >>well has to be amplified prior to "counting" in the A/D
> >>converter.
> 
> Anthony Atkielski:
> >No matter how much you amplify it, you still get discrete levels.
> >Every additional electronic adds one indivisible unit charge.
> 
> Bullshit. No actual MOSFET amplifier used in even a high-zoot
> CCD will feed a signal into the A/D converter sufficiently
> noise-free that the A/D converter will relibly report whether
> 17586 electrons or 17587 electrons had accumulated in a
> given potential well. Hell, the pre-amplification readout
> noise is greater than that. You are simply mistaken. There
> is *nothing* quantal about the signal that leaves the CCD.
> 
> By any practical definition, pixel amplitude is an analog
> signal prior to its interpretation at the A/D converter.
> That's why it's called an A/D (analog/digital) converter.
> 
> Like, duh.
> 
> -Alexey

I love it when my neighbor Alexey gets like that!! Can we have a show of hands
of people who have the slightest clue what these guys are talking about? But I'm
proud to be on the same list with them. Hey guys! IT's Kindergarten! It's show
and tell time!!!
Mark Rabiner