Hi,
I'm confused! For landscape shots, I read to use a polarizer. Then I read to use a neutral density gradient filter.

Here are my questions:
1) Can you match up both filters, one on the other? Is it advisable?

2) If you use one or the other, what are typical situations for each?

3) The "general rule" is to not use a polarizer on a wide-angle lens. Are there any "general rules" regarding the ND filter?

4) I will be traveling to Thailand for 3 weeks in Feb '07 with my 30D & 3 lenses: 10-22, 24-105 & 70-200 IS. Which lens would benefit most from either filter?

Thanks in advance for all your comments.

Anthony

I'd recommend you do some reading to understand what each does and how they work before you shell out the $. These tend to be expensive and will not help your photography if you don't understand how and why to use them.

Polarizers:
http://www.luminous-landscape.com/tutorials/polarizers.shtml

This article on creating the effects of a graduated neutral density filter should explain the basic concept:
http://www.luminous-landscape.com/tutorials/digital_split.shtml