The Canon S100 is a small camera but unlike my Sony TX10 it is not quite small enough to fit in a pocket. It is also not waterproof or dustproof, so a case seemed in order. I made a test with the fabric from James' trench coat and then made the real one in Goretex (left over from James' waterproof trousers). The case is lined with fleece (left over from my blue hoody jacket) and the closure is velcro. It is basically just a rectangle with a lid. The lid has little gussets on the side for extra water protection. It hasn't yet been up in the mountains but I found the case very convenient, and the S100 really became a take everywhere camera as a result.
18 hours ago