Condensation

The local water table is just below the lawn surface where I live (in a dip with a stream) so moist air is a problem all year round.  Since I have a roll-off obs. when the roof shuts the local air is trapped and moisture always settles on the OTA & mount – never the wooden walls or roof. I quickly acquired a de-humidifier and run it on a timer for 3 hours during PM, from mid-Oct to mid Mar.  This allows the air inside to warm up, even on cloudy days, and maximises the efficiency of the de-humidifier.  Everything stays bone-dry!  If I don’t (and I’ve experimented) then mould & rust quickly becomes a problem.