Weatherpoofing and storage.

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Saturday: I went up to check the observatory. To find a wet patch on the floor on the south side of the pier. The mounting was covered in heavy condensation but unlikely to be the prime cause of the wet floor. The dome's shutters are by no means well sealed at the outer edges when closed. Their overall width is critical for sealing where the outer ribs meet. The shutters butt together in the center at the same time as they meet the outer ribs. A central strip overlaps both shutters to prevent direct ingress.

In summer the slightest increase in ventilation will keep internal temperatures down. In winter I need better sealing of the shutters to keep the weather out. I could apply temporary arcs to the slit ribs to close the present gaps.

The floor hasn't been wet during rain before now. So the wetness might have been wind-blown snow. Today is forecast for all day rain. So I shall have an excellent chance to monitor the situation for leakage. The larch floor boards seem impervious to weathering. Once they turn grey they seem not to change. The observatory floor was certainly exposed for long enough for weathering to take place before the dome went on. The boards are intended for decking so could probably do with an oiling.

Fortunately, there was very little wetness on the top ring just under the dome. Normally it would be swimming on the south western side despite the overlapping rubber skirt. The curved extensions seem to have done their job by sealing the former 4" [vertical] gaps. I shall have to give the new timber a mineral treatment to darken them down to match all the rest.

I had a look at adding larch storage shelves at mid wall height on the north and northwestern walls. The midriff 2x4s would provide plenty of support for a 5" wide shelf laid on top and simply screwed down for security. These shelves would not get in the way when I am looking south with the telescopes. Yet would be wide enough to hold long and narrow, snap-top, food storage containers. Plastic boxes would provide direct weatherproofing and mechanical protection without impeding observatory use. Being well below the large radius of swing of the focuser on the 7" f/12.

I am beginning to get a better feel for heavily trafficked areas and those which don't need to be "child-proofed." Safely moving about in the pitch dark needs very careful thought and planning. Projections and sharp corners can easily cause injury when the user is completely focused on another activity. It's no use thinking you can duck under something given enough practice. It never happens! You will bang your head as soon as your mind wanders. Low doors and beams are a perfect example. Only the mounting, counterweights and telescopes offer potential targets for my head.

The LED lighting I have installed is doing its job well. Providing red background light without spoiling my night vision. I have a low wattage bulb inside the pier to highlight the stepladder and the large hole in the floor. [When the hatch is open.] Another overhead bulb washes the entire dome with dim, red light. 

I haven't done much night observing to have needed the string of red led "Xmas lights." They offer very little background illumination but are handy for marking out the borders of the dome and support ring. I am planning to fix them more permanently with staples once I decide on their best location. At the moment they are threaded through the roller support pressings and merely lie loosely on the top ring.

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