Linear Polarizer & cirrcular >>how to differentiate

[goldfish]

I just received "HOYA POLARIZING FILTER" and it doesn't mention whether its

liear "which I want" or circualr ..any one has a practical answer..thanks

alot.

[akira]

Hi,

 

Hoya brand filters are basically the same as those of Kenko brand ones sold in Japan, so the designation system should be identical.

 

If you see "C-PL" designation printed on the outside of the ring, it is a circular filter. If you see just "PL" designation, it is a conventional linear polarizer.

 

Hope this makes sense.

[oceanphysics]

Hold it up to a mirror and look through the filter, at the reflection of the filter. A regular polarizer will look the same (light grey) either way you turn it. A circular will be light grey in one direction and black in the other.

[alan_chan4]

Linear PL works with either side, but circular PL works on 1 side only.

[akira]

Wow,

 

I didn't know that!

 

Thanks for sharing the useful tip, Ocean Physics and Alan.

[david_henderson]

As far as I'm aware, if a camera will work with a linear polariser it will work with a circular as well. Its the reverse that causes problems- if a camera requires a circular polariser to focus or expose properly, a linear will not do.

[goldfish]

thanks alot for the usefull informations.. I checked the filter and I found these letters " PL " & that means its " liear" as AKIRA said.regards