A woman I knew who was also involved in the same scrapbook company told me about a collection of old photos she had inherited from her parents who had long since passed away.My friend explained to me that no matter how hard she tried, she could not figure out who the people were in these photographs.
Dating a photo based on a man's hat can lead you to incorrect results.
With that said, clothing is one resource for you in identifying the age of a portrait but it is not the only source.
Photos taken during the Civil War may have a tax revenue stamp on it.
Jewelry might help date a photo especially in cases where men are wearing fraternal organization medals.
Edin Photo, is a web site that includes a very detailed description of all types of photography processes.
Costume In articles about dating photographs one of the ways to identify them, which is emphasized time and time again, is by looking at your ancestor's costume (or clothing).
This site includes an easy to understand history of 19th century photographic techniques, along with photographic examples.
Photo Tree has an archive of 1,000 photos that you can use to compare your photo and help yourself figure out the date a photograph was taken.
The following are some steps to consider in identifying your old photos.