Advantages of solar etching method

The advantage of solar etching is that images can be permanently recorded on glass and metal plates. Solar etching replaces the complicated process of intaglio or relief printing. Solar etching method is to use natural light instead of lithographic chalk to draw, and directly capture and fix the image.

The photographic method of sunlight etching is more than ten years earlier than that of Daguerre method. In fact, it should be called the inventor of photography, but it has not been recognized because Nieps has refused to disclose it for confidentiality reasons. Scientists at the Getty Research and Conservation Institute in the United States have recently conducted an all-round analysis of this oldest photo in the world, and believe that this photo has been well preserved so far.

The Invention History of Solar Etching

In 1826, Nilpus repeated the above process with a 6*8 inch tin alloy plate instead of glass. After coating, it is put into a camera, and the visible scenery exposed to the sun is dimly focused through the skylight in the courtyard of Burguni's Riverthorne, Xia Long, the hometown of glass in Nilps. After 8 hours of exposure, the images of the two sides of the building exposed to the sun are generated.

The brightest part of the scene is due to the bleaching and hardening of asphalt. During the development process, the partially exposed midtone coating and all unexposed shadow coating are dissolved, exposing the dark gray metal of the tin alloy plate. The result is a positive image, which is the first natural landscape photo and can be preserved in the world.

The asphalt solution used by Nilpus is an asphalt compound, which is used as a protective layer in engraving and lithography. This asphalt can be bleached and hardened under the action of sunlight, eliminating the role of lavender oil (solvent).

Nilpus called the method of obtaining images recorded on glass and metal (1822) by sunlight for the first time "heliography". Derived from the Greek meaning of "Sun God" and "Graves".