Circular Polarizer filter

[Joshua Post]

A neat use for a circular polarizing filter that I got as part of a kit and never used:
http://www.diyphotography.net/weekend-project-magical-plastic-fantastic

I find a lot of good information on that site

[Teresa (pocketmouse)]

wow, this is cool! I have a polarising filter but don't get to use it too much!

[Christopher Byrd]

it's uses are for reducing reflections on glass and water and makes the blue sky more vivid. ...and for finding weak points in glass and plastic.

[molizard]

I have one & when I try to take a picture on a sunny day with a blue sky, I get a hexagon shaped lens flare. I've read that if the sun is behind your back it will have no effect. So I thought 90degrees & that is when I get the lens flare. So it sits in my camera bag......

[Miley]

I accidently discovered this one myself when taking my polarising filter out of the celophane infront of my computer screen... MAGIC!

[Adam Kelly]

You can use two circular polarizing filters as an adjustable ND filter by stacking them, in line it's roughly -4 stops, goes up to about -14 stops when perpendicular