Collecting Early Photography

In early photography, the process is not a technical footnote — it is a large part of what is being collected. Two prints of the same negative, one a salt print of the 1850s and one a later albumen print, are quite different objects with quite different values.

The principal processes

Daguerreotype (from 1839): a unique image on a silvered copper plate, mirror-like, appearing positive or negative depending on the angle of view. Housed under glass in a case or frame. Extremely sensitive to abrasion and to atmospheric tarnish; the seal is protective and should never be opened casually.

Salt print (from the 1840s): the earliest paper process, made from a paper negative. Matte, with the image sitting within the paper fibres, giving a characteristic soft, slightly grainy quality and a warm brown tone.

Albumen print (dominant from the 1850s to the 1890s): coated with egg-white, giving a slight gloss and a purplish-brown tone. The great majority of surviving nineteenth-century photographs are albumen prints. Prone to fading and to a yellowing of the highlights, and often mounted on card.

Ambrotype and tintype: unique positives on glass and on lacquered metal respectively, inexpensive in their day, common in family portraiture.

Carbon and platinum prints (later nineteenth century onwards): both notably stable. Platinum has a distinctive matte surface, a long tonal range and cool grey blacks, and was favoured by pictorialist photographers.

Cyanotype: the familiar Prussian blue, used for botanical records and amateur work.

Learning to distinguish these by eye takes practice and a loupe. Surface sheen, tone, the depth of the image within or upon the paper, and the mount together give the answer.

Print date and negative date

A photograph has two dates: when the negative was made, and when the print was made. They are frequently decades apart.

A vintage print is one made at or close to the time of the negative, and is ordinarily the most valuable. A later print, made by the photographer years afterwards, is worth less. A posthumous or estate print, made after the photographer's death under the authority of an estate, is a documentary object rather than a work by the artist, and should be priced accordingly.

Process is often the best evidence of print date, since processes fall out of use. A print in a process unavailable at the stated date is a print of a different date.

Mounts, stamps and inscriptions

The mount is part of the object. Studio imprints, blindstamps, negative numbers, retailers' labels and pencil inscriptions on the verso all contribute to identification and provenance, and a print removed from its original mount has lost evidence as well as value.

Photograph the verso before doing anything else, and never wash, trim or remount.

Condition

Fading is the principal enemy of early photographic material, and it is caused by light and by residual chemistry from imperfect washing. Look also for silvering, a metallic sheen in dark areas; foxing and staining from poor mounts; abrasion of the surface; and, in cased objects, tarnish and a failed seal.

Faded photographs cannot be restored. What is lost is lost, which is why housing and light exposure matter so much: see [preserving works on paper](/guides/preserving-works-on-paper) and [storage and conservation](/guides/storage-and-conservation).

Beginning

Buy examples in good condition rather than famous images in poor ones. Handle prints only by their mounts, with clean dry hands or nitrile gloves. Read the standard reference literature on process identification, and, where possible, look at material in a museum print room, where prints of known process can be examined side by side. There is no substitute for that half hour.