This essay and manifesto define speculative photography from a historical perspective and through practical poetics, as photography that integrates fantastic and experimental elements in both its subjects and processes. Such photography is even more urgent at a time when generative artificial intelligence (AI) and computational photography are driving photography to an impasse of fabricated yet all-pervasive realism. The text defines speculative photography in its semiotic and information-theory aspects, outlines a taxonomy of speculative qualities in photography alongside examples of photographers and photographic communities practicing them, and pays particular attention to contemporary subcultures of early-2000s digital camera (digicam) reuse and internet pop-cultural redefinitions of “aesthetics”. While theories and definitions of speculative photography have existed since the 1970s, they are scattered and cover only select aspects of the broader concept proposed here. This paper argues that speculative photography rejects empiricism and notions of truth while practicing an art of the “medium” in its most literal – physical, artistic and spiritual – meanings.