What is the most significant difference between Daguerreotypes and Calotypes?

The most significant difference between Daguerreotypes and Calotypes lies in the ability of Calotypes to produce multiple prints from a single negative. This process allowed photographers using Calotypes to create various copies of an image from one exposure, which made photography more accessible and versatile.

In contrast, Daguerreotypes produced a unique image on a polished metal plate that was not reproducible. Each Daguerreotype was an individual image, meaning if one wanted more copies of that photograph, they would have to set up the shot again and re-expose the plate. The ability to create an unlimited number of prints from the same master negative revolutionized photography and laid the groundwork for modern photographic practices.

While other factors, such as the materials used and production costs, are indeed important aspects of the two processes, the key distinction in terms of photographic reproduction is the multiple-print capability of the Calotype method.