When to use a Polarizing filter?

[kbhagat]

When to use a Polarizing filter?

I bought Canon’s Polarizing filter for my 100-400 Zoom. I was wondering if I should have it on anytime I take out door shots, or only when the sun causes reflection from glass and water? Also not sure if it reduce light by one stop or so?

What is a good rule of thumb to use this filter?

[Jeppe]

Well.. you can use a polarizer all the time, but when you have the sun directly behind you or in front of you it wont give any effect.

Also.. it will give you powerful colours in the woods, if there is any light that can be polarized.

For water the best angle for eliminating reflexes is about 30-40 degrees from surface and for blue skyes the best angle is 90 degrees from the sun.

[kbhagat]

Thanks for the reply. I'll try what you have suggested. I'll let you know the results, if we ever get a sunny day here in NJ.

[chris maddock]

As to the light loss, it is up to 2 stops, depending on how much filtration you apply.

KRs
Chris

[onehotrx7]

Well, one rule of thumb is literally that - point your thumb at th sun, with your index finger sticking out like a gun... by rotating your wrist back and forth, your index finger will point to the band where your polarisation will be it's strongest... if the sun was overhead, that would be all around the horizon...

Cheers,
Stuart