Olympus-OM
[Top] [All Lists]

[OM] Spot-metering madness

Subject: [OM] Spot-metering madness
From: "Carlos J. Santisteban Salinas" <cjss@xxxxxxxxxxxxx>
Date: Wed, 12 Feb 2003 23:10:34 +0100
Hi, all.

A while ago I saw on the list a discussion about the (lack of) accuracy of
the OM-4's spot meter with lenses other than the 50mm... but I'm afraid the
thing is worse than expected!

I tried all my glass while metering on a white sheet of paper, evenly lit
by a relatively distant lamp, and compared the average vs. spot readouts.
The spot mode *always* indicated a slower exposure, but the offset was
related to each particular lens. Here are the results:

Sigma 14/3.5:    -0.7 (I mean -2/3 EV)
Sigma 16/2.8***: -0.7
Zuiko 21/3.5:    -1.3 (that's -1 1/3 EV!)
Zuiko 28/2 MC:   -0.3 (only 1/3 EV, the lowest offset, shared by a lot of
lenses)
Tamron 28/2.5:   -0.3...-0.7 (somewhere in between)
Zuiko 28/2.8 MC: -0.7
Zuiko 28/3.5:    -1.3
Zuiko 28-48 @28: -1.7 (-1 2/3 EV... ouch!)
            @35: -1
            @48: -1
Tamron SP28-135: -0.7 (at all focal lengths)
Zuiko 35/2 MC*:  -0.3 (my first Zuiko)
Zuiko 35/2.8*:   -1
Zuiko 35-70/3.5-4.5:
            @35: -1.7 (!!!)
            @50: -1.3
            @70: -1
Soligor 35-140:  -0.7 (at all focal lengths)
Tamron SP35-210/3.5-4.2:
        @35-50:  -0.3
        @80-210: -0.7
Zuiko 40/2 MC:   -0.3
Zuiko 50/1.4*:   -1 (maybe slightly less)
Zuiko 50/1.4:    -1 (id.)
Zuiko 50/1.4 MC: -0.7
Zuiko 50/1.4MC**:-1 (maybe slightly less)
Zuiko 50/1.8*:   -0.3
Zuiko 50/1.8:    -0.7
Zuiko 50/1.8 MC: -0.3
Zuiko 50/1.8miJ: -0.3
Zuiko 50/3.5 MC: -1.3 (ouch!)
Zuiko 55/1.2:    -1
Vivitar 55/2.8:  -0.7
Tamron SP70-210/3.5:
        @70-135: -0.7
        @210:    -0.3 (mostly used at this focal length)
CPC 75-200/4.5:  -0.7 (at all focal lengths)
Zuiko 85/2*:     -0.3
Vivitar 85-205/3.8:
       @85-135:  -0.7
       @150-205: -0.3
Tamron SP90/2.5: -0.3 (another of my oldest lenses)
Zuiko 135/2.8MC: -0.3
Zuiko 135/3.5:   -0.7
Tamron SP180/2.5:-0.3
Zuiko 200/4 MC:  -0.7 (IIRC -- forgot to write it!)
Zuiko 300/4.5:   -0.7

*)   Silvernose
**)  Serial number 1136xxx
***) Full-frame fisheye, maybe not valid for this test.

I repeated some tests on my OM-2S -- same results (both cameras with fresh
357s). Also did a few tests in daylight -- again same results. BTW, most
lenses were set around f/4 and measured exposure (in average) was about
1/30 for ASA 400 -- well within the measuring range.

Maybe some of you can reproduce similar results... or it's just my OM-4
(CLA'd summer 2000) gone MAD??? ;-)

Enjoy,

...

Carlos J. Santisteban

<cjss@xxxxxxxxxxxxx>
<http://cjss.galeon.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 >


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