P3D Re: Rainbow gold

["Kenneth Luker" <kluker@xxxxxxxxxxxxxxxx>]

 Rod Sage  wrote:
> 
> I just thought of a way to profit from stereo photography. Now we can
> all put our knowledge of stereo to use. I was looking at a rainbow this
> afternoon and got a great idea. Imagine taking hyper-stereo pictures of
> a rainbow. By looking at the resulting images, you could pinpoint
> exactly where the pot o'gold is at the end of the rainbow. By the way,
> if the rainbow is complete, is there gold at both ends? Should we use a
> pair of Polaroid cameras so that we get there before the leprechaun
> finds the gold? How wide of a base would you recommend?
> RDS

I'm sorry to say it but were you to pinpoint the gold, you 
could still never get it.  The rays of light coming from a 
point at the rainbow's end into the left lens of a stereo 
camera are at precisely the same angle as the rays 
coming into the right lens, because of the geometry of the 
raindrops, refraction, etc.  Therefore, those lines are 
parallel, and the end of the rainbow mus itself therefore be 
at infinity.  Since you can't travel an infinite distance in a 
finite time, you would never reach the pot of gold.
Ken Luker

_______________________________________________________________
Kenneth Luker
Marriott Library Administration
KLUKER@xxxxxxxxxxxxxxxx


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