Quote Originally Posted by benjiboy View Post
Circular polarizers are more suitable for cameras that have beam splitters in the focusing screen, linear ones effect the the TTL meter reading and the exposure accuracy, linear polarizers would be more suitable to use with a Rollei http://en.wikipedia.org/wiki/Polariz..._(photography)
P.S. the original Rolleipoll polarizer was a linear one with markings on the outer ring to help one orientate it when removing it from the viewing lens and putting it on the taking lens