The first paragraph on dating images in this useful guide begins like this:There exist Facebook groups My Daguerreotype Girlfriend and My Daguerreotype Boyfriend. That’s not the kind of dating I’m talking about.
This gentle humor is a good introduction to Sean William Nolan’s work; what he calls his “labor of love.” His hard work and his scholarship are impressive. In Fixed in Time, available for all through a free download, he methodically lays out the process for making a best guess as to the age of cased daguerreotypes. He has spent years on this and it shows. Copiously illustrated, clear and not fussy or stilted in tone, this is very useable and comprehensive guide. If you have ever wondered about how you might go about figuring out the age of that antique object someone told you was a daguerreotype, or if you are a seasoned collector of these wonderful images, you will find that this is a helpful file to have on your computer.
There is a Facebook page for the guide, and a promise that, for the bother of simply sending Mr Nolan your contact information, you can have updates and access to even more information. Seems a small price to pay for such generosity.