If you rummage through your medicine cabinet, or open a package of just about anything new, chances are you’ll find small moisture-absorbing packets (also known as des-iccant). These packets help keep pills and other medicines dry, as well as suck moisture out of the air within product and clothing packaging. These packets can help keep your photo equipment dry when shooting outdoors, especially in extended humid or damp conditions. (See Figure 1.)
Moisture-absorbing packets or nodules are also called a desiccant, for the moisture-absorbing substance they contain. There are many substances that can absorb moisture, but what we want is a simple way to keep equipment dry. Save the packets and use them when they are new, not when they’ve been shelved for many months. Eventually, depending on the level of surrounding humidity, these packets will lose their moisture-absorbing quality and be useless to you.
For that reason, try to use packets from dated products, like vitamins or pharmacy items, so you have an idea of the expected useful life of the desiccant. If the packets have been directly exposed to moisture though, or feel caked up inside, discard them. Some des-iccants include a chemical that will allow them to change color when the moisture-absorbing quality is expended. So if the desiccant has a color, like blue or pink, it’s also a good idea to discard it.
I have explained how useful plastic bags can be when heading outdoors with delicate camera equipment. Those plastic bags make excellent small environments to keep out humidity. Plastic is porous, though, and moisture-absorbing packets can help keep that small environment even dryer. If you are packing memory chips, lenses, small point-and-shoot cameras, flash units, and so forth, and have to use them in humid air or with sweaty hands, you’ll help keep them dry by placing them back into plastic bags with moisture-absorbing packets in them.
Rice can work well as a desiccant too, although you’ll have to create your own packet of rice. You may already keep rice in a salt shaker to keep the salt dry. The reason it’s so hard to keep salt dry in a humid environment is because salt is also an excellent desic-cant. But salt has corrosive qualities as well, so you wouldn’t want to use salt as a desic-cant around metal camera equipment. (See Figure 2.)
Camera bags, however, can take on an odor when exposed to very humid conditions so when you’ve returned home from a nature or landscape shoot, your bags may have become slightly damp. Letting them sit closed without anything to absorb moisture or odor inside is a bad idea. Open baking soda boxes, the type used in refrigerators, can help prevent odors from developing inside camera bags and gear cases after you’re back home from those wetlands, or that beach, you’ve been photographing.