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Until I bought my Hasselblad 500 c/m I’ve never used a camera that didn’t have TTL exposure metering. Even back in the late 60’s my  Nikkormat FTn had TTL metering. I’m using a Sekonic L-758DR Light meter for exposure but I’d like to try using a circular polarizer. How do you compensate for the polarizer when using a hand held light meter especially as the filter varies as you rotate it? 

There is some variation in polarizers but it's generally between 1 2/3 stops and 2 1/3 stops light loss. I'd just pick 2 stops and call it good until you have more data. The filter factor of a polarizer doesn't change depending on what position it is in as it only selectively darkens things such as a blue sky when it is 90 degrees to the sun or highlight reflections when things are wet. But the overall drop in exposure on a normal object that is not affected by the polarization is the same regardless of where it is turned.

E.J. Peiker wrote:There is some variation in polarizers but it's generally between 1 2/3 stops and 2 1/3 stops light loss.  I'd just pick 2 stops and call it good until you have more data.  The filter factor of a polarizer doesn't change depending on what position it is in as it only selectively darkens things such as a blue sky when it is 90 degrees to the sun or highlight reflections when things are wet.  But the overall drop in exposure on a normal object that is not affected by the polarization is the same regardless of where it is turned.

Thanks for that. I suppose I can fit it to my Nikon and take a measurement then remove it and take the same measurement and the difference is the number of stops due to the polarizer.

Yes, that's a good idea. Just zero out the meter, add the polarizer and see how much underexposure the meter tells you. That's what you will ahve to apply on the other camera.