Filter for 24mm?

Hey, I'm trying to get a polarizer for my 15-85 lens, and can't seem to find a definate answer to if a regular polarizer will vignette at 24mm equivalent?

I am looking at either the Hoya HD or B&W Karacha-whatchamacallit.

Also will the stock lens cap fit on the filter?

You should be fine.

Both my 17-40 and 24-105 have the 77mm threads, and I use the same CPL on both with not vignetting. The lens cap will only fit if you get a filter with front threads also. Some are made without them. - Stu