Olympus OM Spot Meter Model Question

[KidA]

In the manual for the OM spot meter models, it says the spot area being measured is the microprism circle. Seeing as there are different focusing screens, with different size circles: a) does the size of the spot metering change with different sized microprsims? (As if the spot meter reading was filtered differently with different screens - is this even a possibility with the screens used?). And b) if answer to 'a)' is no, which size is the correct one? I'm not sure my spot models came with the original focusing screens.

 

[chriscrawfordphoto]

The focusing screen in the OM models does not affect the spotmeter area; the spotmeter cell is actually behind the mirror, on the floor of the mirror box. It sees through a semi-silvered section of the mirror. The spot is the area of the microprism on the standard 1-13 or 2-13 screen.

 

[eggen]

Hi Guys!
Finnish manual says that the spot area is 2 % of the hole picture area. English manual says
"The spot metering range is outlined by the outer edge of the microprism". According to my experience 2 % is right.
So if You shoot for example with 300 mm tele lens which angle of view is 8 degrees the measurement of the light is very accurate. Assuming the measuring spot is right.

I like very much the multi spot feature.

 

[thuggins]

I don't have the manual handy but 2% sounds about right. The important thing to remember (and the beauty of the functionality) is that you get a spot small enough that it is not contaminated by variations in the lighting of the scene. This allows you to choose the precise metering for your composition.