No Subject

[Greg Erker <erker@xxxxxxxxxxxxxxx>]

>For all considering making, modifying viewers...
>
>     consider... taking apart cheap binoculars!

  Is there anyway to know in advance what the focal length (fl)
of the lenses will be? I know with telescopes the magnification
is objective fl divided by eyepiece fl.

  With 7x35 binoculars we know the ratio of obj fl and eye fl
is 7, but do we know what each fl is?

  I would love some cheap 80 mm fl achromats for my medium
format viewer. Which pair of $29.95 binos should I buy? :)

Thanks - Greg (Glad to be back on the network) Erker
  



------------------------------