In 1851, Frederick Scott Archer, an Englishman, discovered that collodion could be used as an alternative to egg white (albumen) on glass photographic plates. Collodion reduced the exposure time necessary for making an image. This method became known as the 'wet-plate collodion' or 'wet collodion' method. Collodion was relatively grainless and colorless, and allowed for one of the first high-quality duplication processes, also known as negatives. This process also produced two types of positives: the ambrotype and the tintype (also known as ferrotype).