If you’re planning an extended stay in a humid part of the world -- a rain forest, perhaps -- bring along a desiccant. Available in small packets, desiccants draw moisture out of the air. Silica gel is the most common; your local camera shop can probably get it for you. By keeping your camera and film in a plastic bag with the silica gel packet, you protect them from condensation -- even fungus. Believe it or not, fungus can eat away both your lens’s surface coatings and your film’s emulsion.

Another useful item for rainy climates? Protective camera coverings. You can fabricate a “raincoat” for your camera from a plastic bag, or you can buy something more substantial from camera shops or catalog outfits. They sell special plastic shrouds that protect cameras from rain but allow full access to camera controls and the viewfinder. And if you have a digital point-and-shoot, you may want to consider purchasing a waterproof housing for your camera to protect its extra-sensitive electronics.