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[filmscanners] Re: Film resolution - was: Re: 3 year wait



Austin writes:

> > > But, one thing that is VERY important is
> > > there is a difference between sampling sine
> > > waves and square waves.
> >
> > Not from the standpoint of the Nyquist theorem, which applies to any
> > periodic signal of any shape.
>
> Nyquist has nothing to do with amplitude, it
> is only a detection of frequency of a signal.

I don't see any mention of amplitude in the statements you backquoted.

> That is not correct.

Eight years of application of the principle provide strong evidence for its
correctness ... considerably stronger than your assertion to the contrary.

> You do not get any guarantee of accurate
> amplitude reconstruction with 2xf, nor do
> you know what the waveform was.

You know what the waveform of a periodic signal is.  And with two samples
per cycle you can reconstruct it entirely.

> What I said was absolutely correct, and what you
> said here is irrelevant as it applies to film scanners,
> and actually has nothing to do with the accuracy
> of my statement.

I'm not the only one who said it.  It is nearly self-evident.

> Some understanding you appear to be missing is
> that film scanners are NOT "point" samplers.

Either a sample exists, or it doesn't.

> They sample a physical "area", and get an average
> "reading" from that area that the sensor "sees"
> (is in its FOV).

In other words, they take multiple samples.



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