>Meryem--wheels appear to spin backwards when photographed if they
>are spinning at less than 24 times a second (or a multiple of that).
>They would have to spin at exactly 24 times a second to appear to
>be stationary and faster to appear to go forward.  As for "persistence
>of vision," it is rather embarrassing to admit as a co-editor of a
>journal of that name, that that theory ofperception has been disproved as
>an adequate explanation of why we see film as moving, as has the psi
>phenomenon.
 
When we watch TV Persistence of vision comes in to play, but also the
phosphor on the picture tube has a persistence as that little beam sweeps
back and forth turning on and off at various spots of the screen. That's
why I would rather have light letters on a dark background, cheaper
electricity over the years and holds those little accelerated electrons
that fly out of the tubes into my upper organs to a minimun. Your CRT
should last longer too.
 
73, Uncle Art NE Pa.
 
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