The authors present a comprehensive catalogue of 112 known photographs of the Thylacine or Tasmanian tiger (Thylacinus cynocephalus), both from zoological collections and the small number of images that were taken in the wild. Throughout the literature, numerous inaccuracies relating to the provenance of the photographs have entered into publication. These errors often go unchallenged and are blindly replicated in subsequent publications as truths. The perpetuation of such errors can only frustrate or complicate future research effort into the species, hence the need for a reliable reference. This paper provides a summary of the work involved in developing the catalogue, together with a synopsis of the findings. The catalogue has been named the Thylacine Image Registry [TIR], and is published here for the first time.