Photography in the Rain

I'm supposed to do a family photo session this weekend.  But living in Washington its supposed to rain.  I got this recommendation from Scott Kelby (http://www.scottkelby.com/ not a personal recommendation, just off of his podcast) for rainsleeves.  You can find them here.  I will let you know how they work or hopefully I won't have to use one.  They are really small and I plan on keeping one in my camera bag just in case I get caught in the rain and want to take some pictures.