Olympus-OM
[Top] [All Lists]

Re: [OM] Macro Lens

Subject: Re: [OM] Macro Lens
From: PCA Cala <PCACala@xxxxxxx>
Date: Sun, 22 Mar 1998 04:28:05 EST
Hi all:

Based on testing I did at about 1:9 magnification ratio, the 50 mm f/3.5 Macro
Zuiko had a noticable loss of resolution and contrast at f/22, as well as
f/3.5~4  I used to "microfilm" 9" x 9" aerial photo contact prints onto
Kodak's Direct Positive Film (with an E.I. of only 8 of something).  It took
f/5.6 to get a big jump in performance, but the exposure time under cross
polorized photofloods was too long.  So I got the 50 mm f/2.0 and the ability
to shoot at f/4.0 with great results.  I don't recall that I got any better
definition with the f/2.0 at f/4.0 versus the f/3.5 at f/5.6, but it was a
case of getting the right tool for the job.

Sometimes these diffraction degradations (and large aperture limitations) take
comparison tests to detect!  I sold the f/3.5, but there sure are times I
could live with and want the f/22 setting.  I see that the 50 mm f/3.5 Canon
FD I picked up for $27.50 (with FD 25 mm tube) goes to f/32.  Yikes, I bet
that isn't too sharp a setting.

Gary Reese
Las Vegas, NV

< 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 >


<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz