Filmscanners mailing list archive (filmscanners@halftone.co.uk)
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[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.
> Though at Nyquist, you guarantee detecting
> the frequency, you do not guarantee full
> amplitude.
You can reconstruct any periodic signal by sampling it at twice the
frequency of the highest-frequency component of that signal.
> To sample square waves, and GUARANTEE getting
> at least ONE "sensor" that contains full amplitude,
> you MUST sample at 4x f ...
No, to sample square waves and reproduce them with complete accuracy, your
sampling frequency must be infinite, as true square waves contain components
of infinitely high frequency.
----------------------------------------------------------------------------------------
Unsubscribe by mail to listserver@halftone.co.uk, with 'unsubscribe
filmscanners'
or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or
body
|
