Tim;
Fantastic. Best explanation of the process I've seen.
Analogy of course is audio CD players. When they first arrived if I
recall they were '2X' which meant either they sampled at the Nyquist
limit or double it, not positive which. They didn't sound all that good.
Within a year or 2, they were 8X or 16X, ie 4 and 8 times more sampling.
They sound good.
George
HI100@xxxxxxx wrote:
>
> Dear OMer's,
> Here are some comments on the ongoing pixel debate.
>
> chris@xxxxxxxxxxxxxx writes:
>
> << 100 lines per millimetre is 200 pixels per millimetre.
> 200px times 25.4mm is 5080 ppi.
> cjb. >>
>
> In this and previous threads on the number of pixels required to resolve a
> given number of lines per mm, a ** theoretic** number of 2 pixels per line
> is being used. In signal processing this theoretical limit is often termed
> the Nyquist limit. That is, to sample and be able to reconstruct a sine
> wave you need at least two samples per cycle. In reality you need more
> samples unless you want to introduce artifacts.
SNIP
> Regards,
>
> Tim Hughes
> Hi100@xxxxxxx
>
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