In the old days, I had polarizing filters for my film SLRs. As far as I know they were just "polarizing." So I've been looking around for a new PL filter, and all I can find are ones labeled "circular ...

A camera lens filter is pretty much what you’d expect: it’s a physical piece of glass that attaches to your camera’s lens, filters the light before it reaches the sensor and, typically, has an effect ...