A camera obscura is basically a device which projects an image onto a surface.
"The device consists of a box or room with a hole in one side. Light from an external scene passes through the hole and strikes a surface inside, where it is reproduced, rotated 180 degrees (thus upside-down), but with color and perspective preserved."
To implement this into a boat shed, all I would need is a hole in one side and a clear wall opposite to project the image onto. The waterfront scene outside the boatsheds would be interesting enough to project and look at.
(from wikipedia)
Examples of Camera Obscura
I wasn't able to find any written information about projecting the night sky, but I did find a couple of pictures which show it being done. So i'm assuming its possible.
Examples of rooms turned into Camera Obscuras
Gallery Research
