The photograph is the science and art of obtaining

by:ambitionmods     2020-07-10
The word photography comes from the Greek f?? phos ('light') and ??af?? grafis ('design', 'write'), which together means 'design / write / record with the light.' Before the term photography was used, was known as the daguerreotype . And although part of its development was due to Joseph-Nicephore Niepce , the discovery was made ??public by Louis Daguerre , after perfecting the technique. This term is used to denote both the whole process of acquisition of images as its result: the very imagery or 'pictures'. The history of photography began in 1839 with the world wide spread of procedure of the daguerreotype , developed and perfected by Daguerre, from previous experiences Niepce unpublished. The 'Year Zero' is 1839. But his history starts with the discovery of the camera obscura , and research on the blackening of silver salts. The photograph was born in France in a time of transition from pre-industrial society to industrial society, facilitated by technical innovations of the time. Birth also influences the positivist philosophy , which states that every element of nature must be tested empirically. The bourgeoisie is the ruling social class of the moment, using the portrait as a verification tool and affirmation of social ascent. In 1816 Niepce obtained a first negative image is imperfect and unstable, with a pinhole camera. In 1826, gets his first blueprint , based on the asphalt or asphalt. Louis Daguerre is associated with Niepce, to continue investigations. But Niepce died in 1833, and Daguerre continued alone until a reliable and commercial. The daguerreotype was presented in 1839 at the Academy of Sciences and Arts of France. That same year, 1839, discloses the process of daguerreotype world. The system consists of obtaining an image on a surface of silver polish. To save money, usually copper plates were silver, they only needed to have a silver face. The image is revealed with mercury vapors, appearing on the silver side of the plate, which had previously been sensitized with iodine vapor. [1] But it was an expensive procedure, and heavy equipment, and required a high exposure time of several minutes at first. In addition to mercury vapors were actually harmful to health. In 1840 William Henry Fox Talbot developed a negative-positive, another procedure called calotype . Was to obtain a negative role, then by contact was positivism on another sheet of paper. The paper is moistened in an acid solution of silver nitrate before and after exposure and before being fixed. It marked the invention of the photographic copy as a single negative could lead to several positive results. In 1842 the English chemist and astronomer Sir John Frederick William Herschel introduced a process called cianotipia . It was also the first to apply the terms 'positive' and 'negative' to photographic images. In 1819, Herschel discovered the power of sodium thiosulphate solvent around the insoluble silver salts, setting a precedent for use as a fixing agent in photography. Informed Talbot and Daguerre of his discovery in 1839 and that it could be used to attach a permanent image. He made ??the first glass negative in late 1839.
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