A trip to the photographer's studio was generally an occasion for Best Clothes, and some of the duds in 19th century images are pretty amazing when one considers the work that went into them. It might be possible to trace particular styles via publications like Godey's Ladies Book, and thus have a better basis for dating portraits. Here are some examples of especially grand creations of the seamstress's art:

a la mode elegance

Sunday best jet apliquee slightly martial, with a bustle

scalloped elegant Lunenburger major blouse action

plaid was in vogue hoop skirt furs