Freeze.

Frenchman Louis Daguerre’s improvements in photography reached America in the 1840s. Personal portraits were soon the craze, and ‘daguerreotype’ studios sprang up in every city, while traveling daguerreotypists served the countryside. This picture presents the controlled environment of the early studios. It took so long to properly expose a photographic plate that the subject needed a head brace to hold a pose.

Source: A. H. Wheeler, 1893—Prints and Photographs Division, Library of Congress.