I'll be shooting all day with my Canons (outdoors only) in the city tomorrow where the temps should range from 27F - 34F throughout the day, in other words, a few degrees either way from freezing. When entering a warm house from a freezing environment, it's not a bad idea to seal gear in giant Ziploc bags that are cold as well before entering to prevent condensation inside the equipment.
I'll be removing my cameras in and out of my camera shoulder bag very frequently while walking around the city. If the outside temp is say 30F and the inside of the bag is a couple of degrees north of freezing, is this something to worry about? Obviously, ziploc'ing all gear before re-entry into the bag every few minutes is impractical and the Ziploc bags would also need to be out of the camera bag in freezing temps as well to be effective.
A non-issue? Thanks!