Yep, edge fog from loose winding and/or leaky paper edges. Take the advice on subdued light loading. I've been using the black rollfilm film canisters from JandC (25 cents each), and like them a lot. Gave about 25 of them to a friend who shoots a lot of rollfilm while he travels and does nature photography, and he loves them too. Keeps the film a lot safer than plastic bags, and keeps pressure marks off the film too.