Bitumen of Judea is a naturally occurring asphalt used since antiquity as a wood colorant, and in early photography as a light-sensitive coating.
It is a light-sensitive material in what is accepted to be the first complete photographic process, i.e., one capable of producing durable light-fast results.
In 1826 or 1827,[2] he applied a thin coating of the tar-like material to a pewter plate and took a picture of parts of the buildings and surrounding countryside of his estate, producing what is usually described as the first photograph.
[3] The bitumen, initially soluble in spirits and oils, was hardened and made insoluble (probably polymerized)[improper synthesis?]
However, Niépce's famous image of Pope Pius VI was produced first by photo-etching and then "improved" by hand engraving.