Polarizer Question

Montec

Can someone please tell me what the adjustable ring on my polarizer filter is for? It seems to just turn freely and I am not at all sure what the purpose of this is.

Thanks

gluwater

It adjusts the effect of the polerizer. If you look at the sky or at water and turn the ring you will see a difference. It will darken the sky and lessen the reflections on water.

Montec

gluwater wrote:

It adjusts the effect of the polerizer. If you look at the sky or at water and turn the ring you will see a difference. It will darken the sky and lessen the reflections on water.

Thanks!!

wxwax

These circular polarizers are tricky buggers. Seems to me that unless the sun is pretty much square to your filter (in other words, right behind you) you don't get even darkening of the sky. For example, the sun was at about four o'clock on this shot.

pathfinder

For the maximum effect with a polarizing filter, the axis of the sun's rays should be about 90 degrees to the axis of the lens axis.

If the sun is directly behind you or in front of you, you will see no effect from the polarizer.

As you rotate the polarizer element while looking through the viewfinder, you will see the sky get darker or lighter.

With real wide angle lenses ( wider than 20mm or so ), you will see the sky much darker onone side of the image than the other due to variation in the effect of the polarizer due to the variation in the angle to the sun's axis, as seen in waxy's picture.