Olympus OM-3Ti Instructions Manual page 59

SPOT METERING (2)
To ensure correct operation of the spot metering:
In spot metering, it is necessary to put the area
to be metered in the microprism section. If there
is a brighter spot in the microprism section, than
the intended subject, the metering value will be
affected.
If a lens is changed, the light receiving angle for
spot metering also changes automatically. The
angle is narrower with telephoto lenses, and wider
with wide angle lenses. However, the metering
area seen in the viewfinder does not change.
When a zoom lens is used, Spot Metering on the
telephoto side permits metering in narrower range
and that on the wide angle side in a wider range,
thus allowing the users to choose the metering
range freely.
Spot metering area
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