First exposure

Joseph Nicéphore Niépce took the first photograph by coating a pewter plate with bitumen and exposing the plate to light in France in 1827. The bitumen hardened where light struck. The unhardened areas were then dissolved away. The camera has been improved in many ways, and the shape and size has been updated throughout history to fit modern times.






 INTRODUCTION of CAMERA OBSCURA

The camera obscura (Latin; "camera" is a "vaulted chamber/room" + "obscura" means "dark"= "darkened chamber/room") is an optical device that projects an imageof its surroundings on a screen. It is used in drawing and for entertainment, and was one of the inventions that led to photography.
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, upside-down, but with colour and perspective preserved. The image can be projected onto paper, and can then be traced to produce a highly accurate representation.

Using mirrors, as in the 18th century overhead version (illustrated in the Discovery and Origins section below), it is possible to project a right-side-up image. Another more portable type is a box with an angled mirror projecting onto tracing paper placed on the glass top, the image being upright as viewed from the back.

As a pinhole is made smaller, the image gets sharper, but the projected image becomes dimmer. With too small a pinhole the sharpness again becomes worse due to diffraction. Some practical camera obscuras use a lens rather than a pinhole because it allows a larger aperture, giving a usable brightness while maintaining focus. (See pinhole camera for construction information.)