Re: BTFR question

["Dirk Wright" <wright@xxxxxxxxxxxx>]

>
>
>Clive Warren wrote:
>> 
>> Most Olympus cameras meter Off The Film (OTF) TTL with the shutter 
open in
>> their aperture priority "auto" mode.  This would indeed result in 
the
>> metered light passing through the filter twice.
>
>Or reflected off it.
>

OTF measures the reflected light from the film itself and is calibrated 
for the average reflectance of undeveloped film. Since a BTFR filter 
may or may not have the proper reflectance, exposure may be off by a 
wide margin. 

Be seeing you.


Dirk Wright
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