I carry a dslr inside a camera specifiz pouch inside my padded messenger bag constantly I also roll with a macbook somtimes. it is a lot to pull out. but i have wrecked several times. and last times crashed hard enough to bend my bars and break a wheel and a toe clip. but my camera is fine. so it is worth having to open two bags. or drop a camera pouch on the ground to get a shot.

I think someone makes a messenger bag with camera inserts tho. yeah the buckets that go inside of the crumpler bags. http://www.crumplerbags.com/Cart/Vie...stle%20Blanket