Building the Octagon Pt.59 Painting in the details.


By means of cloning I can paint in surface texture "borrowed" from other parts of the same image. In this case the weathered surface of 15 year old plywood cladding boards, with machined grooves at 4" intervals. 

I tried other surface treatments and colours but much prefer this one. The veranda "railings" were added using a simple line drawing tool. As was the border to the door.

Painting a snow white dome on top of a freshly boarded observatory building was absolutely hideous! So the rotating roof needs much more gentle treatment in this rural environment. Unfortunately white is the best colour to reflect solar heat. Black is the probably the worst but many colours have odd absorption behaviour in the Infra Red.

The brand new plywood cladding boards can be given the mineral powder treatment. Hopefully to darken the surface to a weathered finish. Like the shed, but without the very long wait.

Perhaps even the same boards could be used for the roof but sloping to shed rain. While still providing internal clearance for the telescope to swing.

An octagonal roof would need some overhang to ensure no rain can "run down the observatory's collar." An octagon has a smaller radius at the center of its straight edges but overhangs considerably more at the "points." There will be a series of eight rotation points where the relative points and straight edges overlap with large or small overhangs.
A double pitched octagonal roof can contain the radius of the swinging dewshield with reduced use of materials and volume compared with a simple taper. A dome can be thought of as an infinite series of flat surfaces too small to see individually.

I like the idea of an octagonal, double pitched roof for another reason. The panels which form its upper triangles and lower trapeziums are of manageable proportions in a 10' nominal diameter. The roof can thus be safely clad by a person working alone. Assuming, of course, still conditions are chosen to perform the task.

Here I have modified the roof of a gorgeous, old, wooden barn to an equal length, double pitched octagon. How can I simulate small "tiles" or "shingles" without adding massively to the roof's rotating weight or badly increasing solar heat gain? 

Click on any image for an enlargement.

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