OK, I'm at the design concept stage of my obs. It will house a C-11 on a G-11 and be used for visual observing (sin, moon, planets) and videoing asteroid occultations. There is also a chance I could use a 15cm f/8 frac for visual variable star estimates, where the wide unvignetted fov would be an advantage.
I've mocked up an obs a the concrete pad with internal dimensions of 3m x 3.5m with the 'extra' 0.5m used for desks and storage. Having played with the scope in this footprint for a couple of nights it seems large enough for the 1-2 people who will commonly use it. I could possibly trim a couple of hundred mm off each dimension but I think that's risky. I could also go a little larger but that is more cost, more weight in the roof, more shading of the lawn and more view lost.
So, what size are other peoples observatories and how cosy or expansive do you find them?
The other dimension I have to decide on is roof height, but I think that sorts itself. I'm 188cm so I plan to have the underside of the roof 195cm above the floor so I can move around without damaging the rafters with my noggin. With the saddle of the G-11 1.5m above the floor I can observe at the zenith in some degree of comfort and it still fits under the roof in the park position, even while piggy backing a small scope. The end walls will affect low elevation viewing but that is only to the south, where Wollongong lights ruin viewing anyway, and to the north, where the house is in the way. Because the rollers sit under the roof the side walls (east and west) will be lower (perhaps 160-170cm) and should allow views to near the horizon.
My backyard is prone to flooding and the situation could easily get worse over the next decade or two. The water is unlikely to get very deep but I wouldn't be surprised to find 20cm of water flowing through my yard. Therefore I have to use a floating floor, not a concrete slab. I'd also like to have the scope (and floor!) as far off the ground as possible to improve my views towards the horizon. If I was only viewing/imaging DSOs and planets I wouldn't be too worried but asteroid occultations can occur basically anywhere in the sky and so the more sky I can see the higher my possible success rate. Has anyone else tried to put their observatory up on stilts or am I the only idiot/optimist?
Any and all comments welcome. Tell me I'm a fool before I find out the hard way.
