History of Science Museum: Collection Database Search


Collodion Positives

Collodion Positives

The collodion positive is a natural extension of the wet collodion glass negative, invented by Frederick Scott Archer in 1851. Looking to compete with the very successful daguerreotye as a commercial studio photograph, Archer showed the following year how an underexposed or whitened collodion negative, blackened on the back or placed against a black background, looked like a positive. The same or similar phenomenon had been noticed by others, including Talbot, and was also inherent in the optical characteristics of the daguerreotype. It followed that effectively the same collodion process on dark sheet metal rather than glass produced a similar result. The collodion positive on glass was called an ambrotype in America, and the collodion positive on metal, or ferrotype, came to be known as a tintype.

Both had the advantage of being cheaper than the daguerreotype; in fact within a short time they were being produced for a few pence, placing studio portrait photography within the means of working-class and poor people for the first time. In common with the daguerreotype, they were (since they were adapted negatives) one-off images, not capable of duplication, and for proper protection and viewing they needed (especially those on glass) to be packaged in a frame or a little case. This was an advantage at first, as the daguerreotype and before it the painted miniature had established this fashionable concept of the personal portrait as a framed or encased artefact. But before long the triumph of photographs on paper, and of the family album, made the collodion positive seem old-fashioned. The introduction later in the 1850s of the carte de visite (see narrative to 36187), equally cheap and portable but also reproducible, and collectable in albums, democratised photography still further, and prevented the collodion positive from gaining the commercial dominance the daguerreotype had. The cheap and unpretentious tintype however survived well into the 20th century, a simplified process for making them providing the basis for a whole profession of street and itinerant photographers, especially at seaside resorts.

Collodion positives were thus for the most part of limited merit, even when taken in a studio. Commercial photographers were not usually being paid sufficient to lavish the kind of attention upon them (or their sitters) that characterises the daguerreotype portraits; while serious pictorial photographers were seldom interested in unreproducible and inflexible techniques, and the process was rarely taken up by amateurs. For the most part the Museum's small collection, assembled through occasional gifts or their incidental inclusion in larger collections, merely illustrates the routine use of the process for popular portrait photography.

Exceptions can be found, even so, especially in the brief period (about 1855-60) when the technique had succeeded the daguerreotype and not yet succumbed to the carte de visite. A good collodion positive enhanced by hand tinting can take its place alongside a daguerreotype - as one example literally does in the cased pair 91018, one a daguerreotype and one an ambrotype, both of native Americans. The portrait of an American Indian chief (62711), one of those who met the Prince of Wales and Sir Henry Acland in Canada in 1860, is a very fine example, in a richly ostentatious mount and case too. A pair of tinted tintypes in a highly decorative 'union' case (thermoplastically moulded shellac), showing a man and his wife and child (25494), and datable from the patents cited for the case to about 1858, shows how even the tintype briefly matched the daguerreotype as an elegantly presented studio photograph.

The collodion positive process was also used to produce stereoscopic photographs (for example 31520 and 37232), continuing another fashion started by the daguerreotype. Stereoscopic transparencies, and lantern slides (for projection), were sometimes made using the collodion process (19977, 79624); but these transparencies are positive prints on glass, made from negatives, not the direct-positive, reflected-light images for which the term 'collodion positive' is reserved.

A remarkable (but unfortunately broken) image of Henry Hill Hodgson on his four-wheel 'velocipede' (72770) is a valuable pictorial document, as well as an example of a larger than usual (full-plate format) collodion positive, which has been framed and hung on the wall. At the opposite extreme, the tiny piece of glass carrying the image of someone's loved one in a locket (49362) measures less that one by half an inch. The common portrait formats are quarter plate (4¼ by 3¼ inches) and eighth plate.

The earliest datable collodion positives in the collection also represent its most enterprising application: the experiments by the microscopist Joseph Delves to produce photomicrographs in that form (12093, 4 photographs mounted together). They were displayed to the Royal Microscopical Society on October 27, 1852, and are perfectly succesful images of their kind. But the purpose of conveying what was seen through the microscope to colleagues, readers, or an audience at a lecture was to be much better served, as photography quickly developed, by paper prints, photomechanical reproductions, and projected transparencies.

Collodion positives, even more so than daguerreotypes, tend to be anonymous, which is the more surprising when contrasted with the use photographers were soon to make of carte de visite cards to identify and advertise themselves. The two small portraits marked on the backing paper 'T. W. Gough. Photographic Artist' (13610 and 67309) are among the few exceptions in the collection. Gough is known from carte de visite photographs as a portrait photographer in Cirencester. The two photographs taken of William John Minn by his son James Minn, in 1860, are also exceptional not only in being signed and dated, but in the quality of their detail, as well as being examples of the collodion positive process in use by an amateur.

Other narratives:

Related Objects: