If your camera is exposed to excessive humidity, you'll want to make sure it's dried out properly when you pack it away – because it's never fun to find lens-killing fungus on your expensive glass. While most of us do this by carefully wiping down equipment and throwing a few silica gel packets into a kit bag, BRNO has released a range of dehumidifying lens and body caps to do the job.
dri+Cap are lens and body caps which absorb the moisture that could damage your camera gear. The patented devices work by containing a moisture-absorbing silica gel packet within the cap – this prevents fungus and mold while minimizing condensation build-up. But for the most part, photographers just use them as they would any other lens or camera body cap.
O-rings, a bit like the Dust Donut, help ensure the caps maintain a proper seal with the camera or lens; preventing moisture from seeping in while your gear is being stored. Using the dri+Cap is also said to mean your camera equipment can easily be stored at a relative humidity (RH) of 35 to 45 percent, which will prevent the growth of that nasty fungus.
Once the dri+Caps are being used, users just need to keep an eye on the silica gel packets which are contained within. When the packets change color from orange to deep green it means the absorbing power is spent and it's time to insert a new one.
If you like the look of the dri+Cap, they're available now (and have been for a little while now in some countries) for Nikon and Canon cameras and lens mounts. A lens and camera body cap set will cost US$45 while they can be bought individually for $24.