re: #39 Bear

A bit off subject. What is a circular polarizer filter used for? I am trying to take pictures of endangered fish in shallow water. ( pup fish in Devils Hole, Ash Meadows, Nevada ) I thought a plane polarizer would be used but could not find anything other than the circular ones for my camera.

See here: luminous-landscape.com

Everything you ever wanted to know on the subject and then some :)