Re: [photo-3d] Digest Number 328

[Olivier Cahen <o_cahen@xxxxxxxxxxxxxxxx>]

	Your question, as it is now quoted, has no meaning. The Pulfrich effect
has nothing common to the frame frequency. There is no frame frequency
of 24 fps, it is 25 in Europe and 30 in the USA. There is no "stereo
base" in Pulfrich effect.
	One eye, the one with a darker filter, sees its image later than the
other eye. The time difference can be about two milliseconds if the
filter absorbs half of the light intensity. If the filter is on the left
eye, every object moving from left to right would be seen more to the
right by the left eye, this means that it would be seen closer than the
screen. If it moves to the left, it would be seen beyond the screen. All
the contrary if the darker filter is on the right eye. The colors of the
filter has no effect. A filter as simple as one polarising glass suited
for stereo projection is efficient enough.
	You do not need a TV program to experiment Pulfrich effect. Hang any
object to a thraed and make it swing at the end of its thread. With a
filter on one eye, you will see it moving along a circle instead of a
line. Have a look to the street from your window and put a filter on
your left eye. Look at cars moving to the right, you will see them
flying over the street.


>    Date: Sun, 29 Oct 2000 00:22:03 +0200
>    From: "Sergio Baldissara" <winter@xxxxxxxxxx>
> Subject: Re: Re: pulfrich "stereo base"
> 
> I must thank everybody answered my posting, but I now realize I asked the
> wrong question.
> I had to ask: "what's the time lapse (frame lapse at 24 fps)  between the 2
> frames of each stereo pair in Pulfrich movies?"
> The "stereo base" of course depends upon the panning speed, but I must know
> the above figures (in milliseconds or in frames) to set up my panning speed.
> Sergio