Virtual photography method

(A), the essence of illusion

The essential characteristics of photography determine that it is deceptive. The basic principle of photography-pinhole imaging-uses the linear propagation characteristics of light to illuminate an object through a pinhole and present the reflection of the original object on the other side. This new thing is just an illusory shadow, without volume, weight and texture. It is not a real thing, nor is it a "true copy" of the original. This phenomenon was first discovered in Mo Zhai, China. For thousands of years, people have been studying this phenomenon continuously, and the virtual shadow obtained is more and more clear, but it can't be repaired. 19th century, with the great development of human science and technology, the British aristocrat Nipps (1765- 1833) originally devoted himself to improving the newly invented lithography technology, but inadvertently invented the "asphalt photosensitive method". This method is: put the photosensitive material into a black box, and through the photo-hardening effect of white asphalt, the process of educating reliable people needs to be exposed to the sun for up to 8 hours to complete the earliest existing permanent image. This is the first time that humans have obtained and kept an image copy of an object. British willaim henley Fox Talbert (1800- 1877). Talbert got the negative image for the first time in the process of shooting. He stuck the negative image of black and white image with the medicine surface of another unexposed material, then exposed, developed and fixed it, and then got countless positive images with the same tone as the original. Then came the famous Frenchman Louis Jacques Mande Daguerre (1787- 185 1). Daguerre continued to study and develop the technology of predecessors, invented a more advanced and perfect "Daguerre Photography", and successfully applied for a patent for invention photography. He plated silver on the polished copper plate and smoked the silver surface with padding steam to produce photosensitive silver iodide. Put this photosensitive silver plate in the cassette for later use. When shooting reliable people, this kind of silver disk is put into a square box camera with a lens aperture of F3.6, and the exposure time is about 1 minute. After shooting and exposure, the silver surface was developed by mercury vapor fumigation. In the light-receiving part of the silver plate, mercury and silver form a shiny amalgam, forming a bright part of the image. The unexposed part of the silver plate has no amalgam and still exists in the form of silver iodide. After development, the silver plate was fixed with baking soda solution, and silver iodide dissolved, showing a black copper plate, which constituted the dark part of the image.