when it comes to wood, if it is protected with some sort of oil, you´ll be fine when the climate is always one thing or the other. You´d have problems if you were constantly going from wet and cold to dry and hot. So when you bring it in, at least make sure the interior is also humid. Drastic changes in humidity cause wood to crack and warp (normally in a spiral pattern). I have a friend that had some intersting things happen to a $3,000 guitar because humidity wasn´t properly managed. I´m assuming that the wood of the camera has been properly treated, but if the finish on the camera is fairly thick, you´ll have less issues. If the wood is just oiled, then you´ll have to constantly be treating the wood to maintain a healthy finish. Lemon or mineral oil are good choices for treating wood. There are even certain waxes that can help keep the surface more resistant.
Aside from all of this, ebony is a VERY close grained wood so it won´t be quite as susceptible to humidity changes but....
Basically, if you live in humidity and will use the camera in humidity, make sure to store your wood in humidity. Go to a guitar store and pick up a guitar humidifier (pretty cheap) to drop in your camera case.
My father is an expert woodworker by trade, and I was in the woodshop from age 2 so that´s where I picked up this knowledge.
