Polarizing filters

[M38A1]

Tell me about them as I'm considering one based only on I heard they bring out the blue skies if they would normally be washed out as well as bring out contrast of clouds in the sky.

1)Can they go on top of a standard UV filter with no ill effects?
2)Do they only really bring out the sky, ie: make it bluer on washed out Texas days?
3)Do you leave it on in all cases or is it a put-on/take-off item?
4)Does it affect flash use?

Thanks!

[WyoBull]

A lot of people misuse a polarizing filter and think it is only to make the sky a deeper blue and bring out the brighter whites in the clouds. The problem with the blue sky is that depending on your camera angle to the sun when you take the picture, you will have a deeper blue sky to one side of the screen and it will get gradually lighter towards the other side. This does not look natural in print,

Where I use a polarizer the most and it is pretty rare, is to reduce or increase the glare on water shots. Some shots with water in them look better with that glare, or mirror look while at other times you want to be able to look "through" the water. It just depends on your style and what you are trying to communicate.

Regarding your questions above, I would not recommend "stacking" filters. If you are going to use a polarizer, take off your UV filter. And, if you are going to buy a polarizer, be sure get a top of the line filter from someone like Hoya or B&K. I bought a Nikon Circular Polarizer years ago and love it because it has high quality glass.

In your second question, yes,they really don't do anything to bring out brighter colors etc. that I have noticed.

Question three, it is a use only as needed tool so you will have your UV filter on your camera 98% of the time. Like I said above, people can overuse these filters so just use discretion as to when you use them.

I do not know the specifics of how many stops of light you lose with a polarizing filter but I would say you lose at least two stops of light. This would affect flash unless your camera has TTL metering and can compensate for it without you having to do so. You will probably hear from other people on this forum who have more knowledge in this area.

[M38A1]

Thanks!