i've got two questions that hopefully SOMEONE will answer. 1. how bad is it for the camera and lens to be outside in cold weather? how about when i bring it back inside to warmer temperatures? i took my camera out today and it's been getting cold... when i came back in some condensation formed on the glass so i ran back outside and it quickly dispersed. i left my camera on the doorstep with the door open so it could adapt to the change in temperature better and then brought it in. would this cause molding? 2. (not so much a lens care question) my new sigma 17-70mm f2.8-4.5 HSM with the nikon mount keeps hunting. i've missed a few shots 'cause of this... even my 18-55 AF-S kit lens avoids hunting... and focuses a lot faster. is something wrong with my lens or does this lens just hunt more? what causes a lens to hunt?