Keith discussed photographic formats that were available throughout the years in New Zealand and has offered this as an excellent clue for determining the date of when a photo was taken. For instance, the deguerreotype format dates to the 1850s and was produced into the next decade; these were very popular overseas, particularly in America. There are very few surviving examples of deguerreotypes in New Zealand.
Examples of other photography formats:
|Ref: 661-39, Stereograph, 1859?, Sir George Grey Special Collections|
|Ref: 589-27, Carte-de-visite, 1870s, Sir George Grey Special Collections|
Keith discussed the introduction of pictorial postcards and their role which he equated to the modern day text message or email for sending short messages to friends. Postcards were also very popular as a collectible item.
The progression of photographic technology changed the size and composition of the photos. The inclusion of backgrounds and props, the ability to photograph large groups of people and capture landscapes -- this is all information that can assist with accurately dating a photo.
Fashion styles can be a definite clue for narrowing down a time period but Keith cautioned it is not as reliable because of the delay in fashion trends from overseas reaching our shores, as was the case in 19th century New Zealand.
A few books were recommended on the topic:
Dating Family Photos 1850-1920 by Lenore Frost
How to get the most from Family Pictures by Jayne Shrimpton
As well a number of titles by Robert Pols
And lastly, if you have an interest in the invention of photography then you want to add Capturing the Light by Roger Watson and Helen Rappaport to your reading list.