-> | WC> I've heard completely exposed and developed color slide film
-> | WC> will perform this task but haven't personally tried it.

-> Hmmm...very interesting... next project perhaps .

I was really into optical communication for a time
and it was one of the few things I never got round to.

Think it was Forrest Mims who wrote for Popular Electronics
that made mention of using color slide film. 

I got ranges out to over 2,000 feet at night with lenses
and a mere LED before alignment became difficult.
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