Hi all, A month or two back I sought suggestions for a material to apply to the inner surface of my dome's sheet-metal shutter in order to stop condensation.
I eventually settled on a material that the local rubber products chain store sells - albeit at not a cheap price, but it seemed perfect for this application. The material (see photo) is 1/2 inch medium density foam, with a dimpled silver foil on the front and the back has peel-off paper to reveal a sticky surface. The price was close enough to $40/m2.
The side benefit of this material is that by using an upward facing light shining on the shutter (now a silver colour), there is an amazing amount of reflected light, which is very useful when good lighting is required. Of course, when observing, the shutter is open so the internal colour doesn't matter.