This article considers photography’s role as a visual technology and the consequent effects of expanded frames of knowledge. At the very moment human vision and memory were called into profound doubt, photography provided a mechanical, prosthetic extension to perceptual experience. However, as a technology, it contains the potential for both revelation and control. In this article, photography is considered as a technique that: expands human perception; inscribes its own mechanical operations into new visual forms, therefore enframing and encoding visible knowledge; and can be harnessed as a disciplinary instrument and technique of power. As a consequence, photography's revealing of hitherto invisible dimensions of reality unfolds within a history of revelation, spectacle and power.