In thinking about the recent "backwards wagon wheels on TV" discussion
here, I remembered another similar effect which can only be seen on
television. A guy was to be interviewed on TV, so he had a special T-shirt
made up for the occasion. It had some sort of artwork (the word
"science"?) rendered in fine horizontal black and white stripes. This was
placed on a matching grey background, so from a distance the shirt simply
looked grey. When his attire was viewed by a TV camera, the stripe
artwork became extremely visible again, full of shifting black and white
bars which flickered and raced along at his tiniest motion.
Believing that TV interviews should always be educational, I thought I'd
help spread the idea.
Another possibility: if fine black and white VERTICAL stripes are used,
and if they get close to the 3.57MHz color encoding frequency used by
NTSC television (227 vertical stripes across the screen), then the
striped area will be seen as glaring *color* moire patters which flicker
and shift. This will even work if the camera is B&W, as long as the
tape is viewed on a color monitor.
With careful use of a paint program, I bet it is possible to include
both effects, as well as color pinwheels and moving bars which go in
opposite directions, crude animations (two words which appear
sequentially), etc. The phase mismatch between TV camera and T-shirt
art determines the color and motion direction, so a bit of detailed work
could create all sorts of TV-signal shennigans racing across your
apparently grey clothing.
One might even consider making some custom laserprinter wallpaper in
preparation for any upcoming interviews.
One final word: "distance learning" (:o
((((((((((((((((((((( ( ( ( ( (O) ) ) ) ) )))))))))))))))))))))
William J. Beaty DESIGN ENGINEER
beatywj@ch.etn.com INDUSTRIAL PHOTOCONTROLS
EATON/CUTLER-HAMMER Everett, WA 206-353-0900