I'm in the middle of disassembling my first Zuiko, a fungussy 50/1.4 SC that
seemed good only as a practice piece. The helicoid grease *definitely*
makes the difference in focusing feel and damping. Wiping off the excess
grease (and there ain't much) loosens damping considerably.
The threads have remarkably close tolerances and a tiny amount of grease
effectively does the entire helicoid. A cleaning and fresh lube would make
all the difference.
Different weight greases could be used to tune the focusing for colder or
warmer climates, but it would be best to find out which greases are suitable
for lenses. I've used certain greases designed for spring piston airguns -
they've proven to resist migrating or liquefying. But more suitable stuff
may be available from Fargo Enterprises.
The only other factor might be a burr in the threads, entirely possible - I
sliced my finger on a tiny burr in this lens. Didn't even notice it for a
while, the burr was so tiny and sharp.
Now I just need to fabricate the appropriate key to turn a couple of tricky
lockrings - not sure this lens is worth the trouble...
===========
Lex Jenkins
===========
From: Chip Stratton <cstrat@xxxxxxxxxx>
Date: Sat, 06 Jan 2001 20:02:45 -0600
A large part, I think most, of the focusing resistance in our lenses has to
do with the helicoid grease which is there to give that resistance.
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|