Camera lucida, 19th century drawing Diagram
A camera lucida was an instrument consisting of an adjustable rod, which was attached to the drawing table with a clip. On the top was a metal prism attached. By correctly adjusting this prism, the scene or object was projected onto drawing paper in the desired dimensions. The image obtained was light-arm and probably the camera lucida found this to be low. The device was in circulation in the nineteenth century. Episcoop
Much later, a projector (the same principle), the episcope, appeared. This device consists of a holder or housing with an adjustable projection lens and a (sometimes two) lamp (s) with a mirror below 45 °. It is placed on an image (postage stamp, coin, photo, etc.) with the open bottom, whereupon it is projected large on a screen (or sheet of drawing paper).
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