[benbreen]

Right, and it's worth pointing out that even Italian renaissance artists from the 15th century, presumably working without the same optical technologies, were still using techniques for duplicating images. It was very common for instance to make a full scale mockup on paper, then punch holes along the lines and rub charcoal in them to make an imprint on the canvas before painting. Not to mention the fact that engraving and printing are themselves new technologies for duplicating images in the same period, so it was clearly in the purview of artists to think about this sort of thing from a technical as well as artistic angle.

The more I think of this stuff the more I love it as an example of the incremental nature of technology - photography wasn't just invented in a certain year, it was a process over about two centuries of experimenting with ways of replicating images that finally converged with advances in chemistry to lead to a breakthrough that we then demarcate as the beginning of a new era. But in some ways it was just the culmination of a process of optical and artistic tinkering that goes back to the early Renaissance (or arguably even earlier, with Grosseteste's experiments with lenses in 13th century Oxford).