Search results
Results from the WOW.Com Content Network
Silver iodide is an inorganic compound with the formula Ag I. The compound is a bright yellow solid, but samples almost always contain impurities of metallic silver that give a grey colouration. The silver contamination arises because some samples of AgI can be highly photosensitive. This property is exploited in silver-based photography.
Calotype or talbotype is an early photographic process introduced in 1841 by William Henry Fox Talbot, [1] using paper [2] coated with silver iodide. Paper texture effects in calotype photography limit the ability of this early process to record low contrast details and textures.
The silver iodide in its unexposed condition was insensitive to the red end of the visible spectrum of light and was unaffected, but the latent image created in the camera by the blue, violet and ultraviolet rays color-sensitized each point on the plate proportionally, so that this color-filtered "sunbath" intensified it to full visibility, as ...
Niépce died suddenly in 1833, leaving his notes to Daguerre. More interested in silver-based processes than Niépce had been, Daguerre experimented with photographing camera images directly onto a mirror-like silver-surfaced plate that had been fumed with iodine vapor, which reacted with the silver to form a coating of silver iodide. As with ...
The "calotype", or "talbotype", [10] was a "developing out" process, Talbot's improvement of his earlier photogenic drawing process by the use of a different silver salt (silver iodide instead of silver chloride) and a developing agent (gallic acid and silver nitrate) to bring out an invisibly slight "latent" image on the exposed paper. This ...
A silver halide (or silver salt) is one of the chemical compounds that can form between the element silver (Ag) and one of the halogens.In particular, bromine (Br), chlorine (Cl), iodine (I) and fluorine (F) may each combine with silver to produce silver bromide (AgBr), silver chloride (AgCl), silver iodide (AgI), and four forms of silver fluoride, respectively.
Daguerre continued to perfect the process to render a unique image using iodine, not to intensify the image, but because of its photosensitivity when applied to silver plates as a vapor. This led Daguerre to the daguerreotype process, in which mercury fumes brought out the latent image in the silver iodide on plates exposed to light in a camera.
Calotype paper employed silver iodide instead of silver chloride. Calotype was a developing out process, not a printing out process like the salt print. The most important functional difference is that it allowed a much shorter exposure to produce an invisible latent image which was then chemically developed to visibility.