P3D Re: Lens Matching

[erker@xxxxxxxxxxxxxx (Greg Erker)]

A data point on modern lenses:

  A friend recently tested about 12
Tominon 127mm f4.5 lenses that were
made fairly recently (5 years perhaps)
for a Polaroid closeup camera.

  He was attempting to match up pairs
for other friends who are planning on
making medium or large format stereo
cameras using them.

  He put the lenses in his 4x5 enlarger
and measured a projected image. He
got a range 531 to 535 mm. This is about
0.75% difference from smallest to largest.
Quite a tight tolerance I'd say.

  It is possible these were all from
the same batch so it may not prove
anything about lens focal lengths
over a long production run.

  If you want to see what this lens
looks like, and the use I'm putting mine
to, go to:
http://www.angelfire.com/ca/erker/bronica.html

Thanks - Greg E.



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