Bill Haynes took a photo of the Mark IV installation, reproduced at ftp://ftp.nofs.navy.mil/pub/outgoing/aah/tass/nofstele.jpg That is the 1.0-m dome in the background. The Mark IV pier is about 4' off the ground, not enough to prevent dew formation during our wet season. Anyone have a good idea as to how to clean water spots off the objective? Arne