strange idea....

[Fraser, Colin J]

> -----Original Message-----
> From: Carlos Vila Deutschbein [mailto:si04697 at salleURL.edu]
> Sent: 22 December 1999 11:42
> To: Budweiser [FTS]
> Cc: Synth-DIY
> Subject: Re: strange idea....
> 
> 
> BTW Moire is somewhat different. It happens on TV screens 
> when for example
> a guy wears a fine-checked jacket. these quick black-white transitions
> (HF) interfere with the colour processing and produce strange 
> patterns.

The rippling effect caused by rapid black-white transistions is actually
caused by the filter that separates the luminance and chrominance signals
from the composite video signal.
The slope of the filter needs to be very steep, so a bit of feedback must be
used
What you are actually seeing - the ripple - is analogue filter resonance in
the visual domain.

I wonder how a filter with adjustable cutoff and resonance would look...

:-)


Colin f