I bought an inexpensive “waterproof” camera. It’s cheap piece of crap film camera inside a case. The case has a gasket. The commentary on the purchase page suggests to coat the gasket with “silicone grease” to improve water tightness. It’s definitely not water tight out-of-the-box! Found that out the hard way.
I trundled down to the hardware store and asked for silicone grease and was handed a can of WD40 “Silicone.” When I explained its application (that I don’t want to spray the entire inside of the case) the salesperson offered Silicone Dialectric Grease, but went onto say that it would destroy the plastic and not stand up to salt water.
I also use this to coat my neck to prevent chafing rash from latex and neo gaskets. In the winter, a layer of grease on the face helps prevent “gasp reflex” in cold water immersion.
Your goal is to create uniform pressure on the gasket. Just close the case on the Fuji paper. The darker spots are the high spots, sand those areas down a bit. When you can close the case and get the same color around the edge, then it won’t leak. But depending on the rigidity of the case and how that hinge distributes the forces it may not be possible. Adding a layer of carbon fiber to the case might help.
OK, thank you everyone. Just out of frame of the photograph there is a clasp that folds over the part of the case that is most prominent in the photo and seals it to the other half of the case.
