We have no idea what generation they are from. Photo may have been taken in Woodstock, Ontario or even in Nova Scotia, where Richard Marple settled as a United Empire Loyalist in 1784 after the War of Independence. It is the only tintype we have ever had and the old folks who had the information are long dead. Thank you so much for your help.
The two date estimates you have provided, thank you so much, appear to place this photograph in the time period of my grandfather, in his 20s, in Woodstock, Ontario. It could be one of his brothers. I am checking our family tree for possibilities. I am puzzled about that because another very early photo of my grandfather at his workplace was not a metal plate. As I read just now on the roots site, the metal plates were popular for just a brief time. Perhaps they were used only for studio camera sittings. I am sorry about the darkness of the image. It looks like black ink was splashed over it, too. Or perhaps something else damaged it. Thanks so much for attempting to restore it. I very much appreciate your patience and kindness.