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Re: Monitor video output

A quick and dirty way to  get projected images of any high-res  screen
might be to simply point a cheap  video camera at the screen and  hook
the camera to the projector.  Probably want to use big fonts.  (Why is
it OK for a computer-generated image to show lots of information  when
everyone tells you to keep your vue-graphs to five bullets max?)

If the vertical sweep frequencies produce annoying beat bars  crawling
up or down the image, try turning  the camera on its side so that  the
scan lines in the two system are  at 90 degrees.  If that works,  tilt
the projector on the same side to bring the image right side up again.
If you can't/shouldn't  tilt one  of them,  put some  extra optics  in
front of its lens to rotate its  image 90 degrees. Look in the  Edmund
Scientific catalog, or browse Peninsula  Scientific in Palo Alto,  for
things like a Dove prism.   Or use two first-surface mirrors  arranged
like a sideways-looking periscope.  They  may be cheaper than a  prism
big enough to fit a large projection lens.