This archived Web page remains online for reference, research or recordkeeping purposes. This page will not be altered or updated. Web pages that are archived on the Internet are not subject to the Government of Canada Web Standards. As per the Communications Policy of the Government of Canada, you can request alternate formats of this page on the Contact Us page.
At the outset photography was slow to react to light, did not register all of the colours in the spectrum, and produced monochromatic prints. Slow photographic emulsions meant action could not be photographed and long exposures in the studio gave a typically dour, non-smiling look to portrait sitters. Emulsions were also most sensitive to blue light, meaning that many 19th-century landscapes show no clouds, but instead have washed-out skies. Signs written with red paint appear dark and unreadable. And for the first 15 years or so, the most popular photographic processes -- daguerreotypes and ambrotypes -- provided only single copies of images. These problems were overcome, but slowly.
A system of making good negatives, introduced in 1851, allowed photographers to make many print copies and incidentally reduced the cost of photography. Photographic sensitivity increased over the years so that "instantaneous" snapshots could be taken by the 1890s. Panchromatic films, registering all colours equally well, became commercially available in the early 20th century. Many different methods of making full-colour images were tried and commercialized from about 1905 on, but the only one to survive was the Kodachrome transparency, introduced in 1936. Early colour prints were problematic, as they initially had to be handmade; later, machine-made prints were problematic as they had a tendency to fade or change colours. At the beginning of the 21st century a whole new form took shape: digital photography, full of promise and possibilities.
The materials for photography were originally quite expensive, so most photographers were professionals who sold their work to paying customers. Initially, these customers were the rich who sat for portraits they would earlier have commissioned as paintings. During the 1850s, glass-plate negatives reduced costs and widened the scope of photographic work. Photographers recorded buildings, places, events and famous people -- all for sale. By the 1890s the Kodak revolution ("You press the button, we do the rest") made it possible to take one's own "snaps."
The halftone and other printing processes allowed photographs to be used in a pictorial press. Advertising using photographs abounded; companies illustrated catalogues and cities published pictorial "puffs" promoting their progressiveness. Cartographers created maps based on photographs; scientists extended human vision through infrared, ultraviolet, and time-exposure photography; generals planned battles by studying aerial surveillance photographs; agronomists and foresters plotted vegetation growth conditions from false-colour satellite imagery. Drivers' licences and other identification included photographs of the bearer -- in short, virtually all fields of human activity have used and been affected by photography.