Negative/positive
A picture taken using a chemical process will produce a negative image when the lightest and darkest tones of the image are reversed. In order to reverse the tones in a negative, it is necessary to make a duplicate or print. Although it was Fox Talbot who came up with the idea for this process, Sir John Herschel coined the terms "positive" and "negative" to describe the process. He was also the one who came up with the term "photography."
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