Ch. 10 History of Photography

This was a darkened room with a pinhole opening to the outside. It was used for tracing images that were reflected through the opening upside down. Later it was fitted with a lens and was reduced to box sized.

• Camera obscura

• Daguerreotype

• Brownie camera

• Calotype

What was the problem with the camera obscura?

• The image was not permanent.

• The exposure couldn't be stopped.

• The exposure time was too long.

• The image was not permanent and eventually, the exposure couldn't be stopped.

When was the first permanent photo taken?

• 1926

• 1826

• 1726

• 1900

Who invented the process called heliography?

• Joseph Nicephore Niepce

• Louis Jacques Mande Daguerre

• William Henry Fox Talbot

• George Eastman

The disadvantage of this process was that exposure time took hours.

• Heliography

• Daguerreotype

• Calotype

• Collodion Wet Plate Process

This used a small portable box with a copper sheet that was plated with polished silver. The silver side was placed down over a container of iodine crystals in the box. The crystals produced a vapor which reacted to the silver and this produced a light sensitive compound, silver iodide.

During exposure, no image could be seen. However, it appeared when the image was developed over a dish of heated Mercury.

• Heliograph

• Daguerreotype

• Calotype

• Collodion Wet Plate

A portable camera obscura was fitted with a sheet of pewter coated with bitumen and lavender oil. Light hardened the bitumen on the bright areas and left it soft and soluble in the dark areas. The dark areas were then removable.

• Heliography

• Daguerreotype

• Calotype

• Camera Obscura

• Collodion Wet Plate Process

Sensitized paper was exposed only long enough to produce an invisible image that would show up when developed. Silver iodide was mixed with gallo nitrate of silver.

The fully developed paper negative was put in contact with another sheet of sensitized paper, both were exposed to light and this formed a positive image.

• Camera Obscura

• Heliography

• Daguerreotype

• Calotype

• Collodion Wet Plate Process

Who invented the Calotype?

• Joseph Nicephore Nice

• William Henry Fox Talbot

• George Eastman

• Peter Henry Emerson

A mixture of collodion and potassium iodide was poured onto the middle of a plate. The photographer held the glass by the edges and tilted it back and forth from side to side until it was coated evenly. Then, the plate was sensitized by being dipped in a bath of silver nitrate. It was exposed for a latent image while still damp, developed in pyrogallic acid or iron sulfate, fixed, washed, and dried.

It was coated on glass and it produced a negative image from which a positive image could be printed on albumen coated paper.

• Gelatin Emulsion Roll Film

• Collodion Wet Plate Process

• Autochrome Process

• Calotype