Outside storage and humidity

I've been considering an outdoor shed for my scope (a Celestron 9.25 CPC), but living in a humid climate makes me wonder. How does one protect against the ravages of humidity?

home depot has a product call "Damp-Rid. These are used in closet to keep cloths fresh in high humidity areas. I've used them second season in my observatory when I notice the high humidity and I live in the Arizona desert. Also if you have power to your obsevatory you can use a dehumidifier. I had to purchase an AC unit to keep my building cool below 90 degrees F. for more info you may call or leave number for more help on this problem. My number is 520-705-9478 (robert)