Against the background of recent discussions of the artist as reader, artisanal literacy, and the role of reading, drawing, and writing in Renaissance workshops, this Working Group chapter project explored artists’ readings of optics, and their methods of annotation, note-taking, and excerpting borrowed from humanists. Most artist-readers, like other artisanal or vernacular readers, engaged with texts in a piecemeal fashion. They were also more likely to encounter optics cut and pasted as parts of recipe collections or books of secrets, which flooded the print market in the sixteenth century. Recipes and secrets were transforming vehicles for the transmission of optics. In this process of transformation, optical knowledge was decontextualized and the received conceptual apparatus of perspectivist optics was left open for interpretation and creative misunderstandings. As a consequence, readers of books of secrets and recipe collections gained a different image of optics than that of more exceptional and scholarly readers engaging with "complete" texts of perspectivist optics. This project investigated the Renaissance culture of optics—farther removed from the university, and more typically found in artisanal workshops—defined by artisanal recipes and optical secrets.