Question on filter size

[cutedude43]

Hi,

I have a Canon Digital Rebel XT with a canon 15 - 55mm lens and a Tamron AF 28-200mm.

I was going through the forum and many have suggested to buy a circular polarizer filter . This is the first time I am buying a filter. How do I decide the filter diameter? I would like to know whether I should go for a 55mm filter or a 58mm filter.

Any information on this will be appreciated.

Vinod.

[coldrain]

The filter size depends on the lens you want to use it on. You can buy step down rings to fit bigger filters on smaller lenses, but this is a hastle to say the least.

[cutedude43]

Thank you. I have just decided to buy 1 circular polarizer for the 15-55mm canon lens.