The Sinden Optical Company (SOC) had considerable success in the production of camera obscuras. The following is taken from the original SOC website and was almost certainly written by Dave…
The instrument produces an image on a curved horizontal screen placed in the centre of a darkened room. Observers stand around the screen, looking down at a convenient angle. The viewing screen is curved for the same reason that the retina of the human eye is curved. The image is luminous and in full colour, with movements the outside screen reproduced exactly as nature. In good light conditions the image is filled with luminous delicate colour. Subtle, seductive and very beautiful in its nature. This is “real” light and living colour painted directly onto the screen by nature itself. Sunsets with the Camera Obscura can be quite breathtaking beyond words!
SOC went on to produce a number of camera obscuras including:
The national Garden festival in Gateshead.
The TaviraTower, Cadiz.
The Castelo de S. Jorge, Lisbon, Portugal
ForedownTower, Hove, E Sussex
The SOC website goes on to say..
Our large Camera Obscura is designed and engineered to last for a very many years with the minimum possible maintenance. The main lens of our instrument is an astronomical aplanatic which is normally made about 12” in diameter and with a focal ratio designed to suit the proposed building. The instrument can be rotated in Azimuth and Altitude so as to cover the whole horizon. The concave screen is usually about 2 metres diameter and can be raised or lowered to control the focus over a large range. We supply and install the complete instrument including the viewing screen. We can advise you on building modifications and arrangements necessary to accommodate the Camera Obscura.