Photography [Greek. "phos" - light; "graphein" "graphein" - to write, inscribe) is an optical process for permanently reproducing objects. A negative is projected on to a light-sensitive medium and permanently fixed there. The basic technology of photography was developed by Niepce and Daguerre of France and publicly launched in Paris in 1829. Daguerre used silver plates exposed to iodine as the support for his pictures; hence the name daguerrotype for early photographs on metal plates. From about 1860, however, glass negatives were used instead of metal plates and they could also be copied. Synchronously with Daguerre, W. H. Fox Talbot, an Englishman, developed a process for making photographs on iodized silver paper (calotype, Talbotype). The Scottish painter D. O. Hill is regarded as the founder of art photography; he used pictures produced by the Talbotype process ca 1843-1845 as preparation for the portraits he painted and ultimately photography for its own sake.