Sacrificed an old 2 gallon Ziploc bag to test this. Backed the camera into the two-gallon bag and cut a hole for the viewfinder. Found I didn't need any access to use the controls on the camera. That could be done right through the plastic. If you want to custom fit it you could use some masking tape to snug it around the lens, making sure it has a "shelf" over the lens to keep the rain off - same thing with the viewfinder area.