Circular Polarizing Filter

wavecaller

Two questions. I have a cheap Circular Polarizing Filter. The camera cannot focus though it is it like an ND filter where you have to focus then put it on. And second, can you recommend an inexpensive but good quality Circular Polarizing Filter? Thanks!

bruto

The camera should be able to focus through a circular polarizing filter, but make sure you understand that "circular" refers here not to the shape but to the physics of the polarizer. It must say "CPL" or denote that it is circular. A linear polarizing filter will look just the same. A linear polarizer can mess up both auto focus and metering.

If this is labeled as a circular polarizing filter, and does not work, then I'd suggest it's just no good. A good one should work.

Hoya is one maker whose stuff is decent but not too high in price, and you're likely to find a Hoya filter good. Various others exist, some quite expensive, some cheaper. Vivitar makes a couple of different grades, of which their less expensive one is reputed to be pretty lousy, their better one decent. I have one of the fairly decent ones, and it works OK. For a general look at what is out there, I'd try the B&H web site. They carry lots of brands and their catalog is very well organized. They also ship fast. Even if you don't buy from them, they're a good resource for research.

An ND filter hampers focus only because it's so dark. A light ND filter up to about #4, may still allow AF in daylight.

Remember that if you have a kit lens with a rotating front element, you must make sure the lens has stopped focusing before you adjust the polarizer, since its effect is changed by rotation. It's inconvenient, but you can still use a polarizer easily in manual focus or back button AF, and not too inconveniently in single servo AF if you hold the focus while you rotate the filter.

wavecaller

Thank you!