Blur Map possibilities?

Can you create a b&w map or mask to affect the value of a blur filter. I have a bkg that I would like to blur parts of but not all of and would like to know how to acomplish this - I am not very expierenced yet with AFX but learn very fast so any ideas or dirrection would be great - where are other AFX forums? - thanks.

(sorry about the double post!! oops)

well, you could ...blur one , then have a clean one underneith.
then use a mask on the blure ones to show the clean one under it and feather the masks for a nice drop off. Lot of wasy I tend to use that one .

.............

Make your b&w map to be the size of your comp.

Then, apply your blur effect to an adjustment layer.

Put the adjustment layer directly beneath your "map."

Then, change its transformation mode to Luma Matte or Inverse Luma Matte, using your "map" as your matte.

-Chris

i prefer the method above, but you can also use a compound blur. It lets you choose a greyscale map for your blur.