CARTE DE VISITE
CARTE DE VISITE - A type of small photograph printed on a thin photograph paper, which is then mounted on a thicker paper card, commonly known then as an albumen print. The prints were the size of a visiting card, measuring overall 2.5" x 4". Carte de visite became very popular in 1859 and were traded among family, friends & visitors.
TWIN-LENS REFLEX CAMERA (TLR)
A type of camera with two objective lenses of the same focal length. One of the lenses is the taking lens, which takes the picture, while the other is used for the viewfinder system, which is usually viewed from above at waist level. A reflex mirror is also used to allow viewing from above, enabling the camera to be held much more steadily than if it were to be held in the hand.
GELATIN EMULSION
Photographic film is a strip or sheet of transparent plastic film (negative) base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals. There were many advantages of the dry plate process over wet plates. Photographers could use commercial dry plates off the shelf instead of having to prepare their own emulsions that use numerous chemicals, beakers & liquids all mixed in a mobile darkroom, many times causing health issues. Dry negatives did not have to be developed immediately, where wet plates had to be used within ten minutes of preparing.
HIGH SPEED PHOTOGRAPHY
Multiple cameras are used to capture motion in stop-motion photographs. This is done by using a row of cameras with trip-wires to make a high-speed photographic analysis. The first subject was that of a galloping horse. Each picture is taken in less than the two-thousandth part of a second, and they are taken in sufficiently rapid sequence (about 25 per second). Once put together, they constitute a brief real-time "movie".