Category
Identification & Dating
How to Identify a Daguerreotype, Ambrotype, or Tintype
The three great direct-positive processes of the 19th century look similar at a glance but differ in support material, surface, and weight — here's how to tell them apart by eye and by hand.
Dating Antique Photographs by Card Mount and Studio Format
Once photography moved to paper prints on card, the size and style of the mount became one of the best clues to when a photograph was made.