Digital photo - impressions of cars and motor bikes

The Invention of Photography

The necessary first breakthrough in photography was in a different, not eye-centered area—that of making permanent photographic images. Employing data from the researches of Johann Heinrich Schulze—who, in 1727, discovered that silver nitrate darkened upon exposure to light—Thomas Wedgwood and Sir Humphry Davy, early in the 19th cent., created what we now call photograms. These were made by placing assorted objects on paper soaked in silver nitrate and exposing them to sunlight. Those areas of the paper covered by the objects remained white; the rest blackened after exposure to the light. Davy and Wedgwood found no way of arresting the chemical action at this stage, however, and their images lasted only a short time before darkening entirely.