Old Vintage Cameras: Black and White Photo Gold Mine Tour Bus

Sunday, March 25, 2012

Gold Mine Tour Bus

Black and White Photo Gold Mine Tour Bus

"Are You Getting Your Share?"

View and Purchase This and Other Great Vintage Black and White Photos, Cabinet Cards, Greeting Cards, and Stereoviews at Retro Vintage Bazaar - On-Line Vintage Collectible Shopping

What is a Camera Obscura?

The camera obscura (Latin; camera = vaulted chamber | obscura = dark, thus darkened chamber or room) is an optical device that projects an image of 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 color 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 History 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.