Leica has a new 8-12 binocular that is supposed to be Leica-water-proof. Be
interesting to see how their internal focus accomodates the variable
magnification feature. Their regular line is sealed and nitrogen-filled.
Perhaps someone will one day make camera lenses that way too. OOOps! Did I
say "Leica"?
LEE
----Original Message Follows----
From: Jim Brokaw <jbrokaw@xxxxxxxxxxx>
Subject: Re: [OM] ( OM ) Dust in lenses
on 6/14/02 5:29 AM, Roger D. Key at rdk@xxxxxxxxxx wrote:
>
> I guess that that is a big plus point for two-touch zooms; no pumping!
>
> Sincerely,
> Roger Key
>
>
>
> Good point. The zooming action has the inside of the lens acting almost
> like a bellows, pumping air in and out.
> _________________________________
> John Hermanson www.zuiko.com
> Camtech, Olympus Sales & Service since 1977
> 21 South Lane, Huntington NY 11743-4714
> 631-424-2121 For Free Olympus manuals,
> please call 1-800-221-3000
Roger, the pumping is fromt the group of element inside the lens moving...
whether the zoom is one-touch or two-touch, there are still a group
(sometimes more than one group) of elements moving inside, displacing air
and 'pumping'. The only way to eliminate this would be internal focusing and
zooming using -electrical connections? -magnetic coupling? I'm not sure
anyone has ever done that, maybe NASA for space?
--
Jim Brokaw
OM-1's, -2's, -4's, (no -3's yet) and no OM-oney...
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