Medir la luz: La evolución hacia el fotómetro moderno

Abstract

The present article is an overview of historical research regarding the light meter performed throughout several foreign research centers, libraries and patent registries. In this article we include several unpublished materials that have been requested from multiple patent and library offices. The light meter is a recent invention of somewhat unclear and understudied origins, despite it being an essential tool in the photographer and cinematographer's arsenal, since only with it can he determine a negative's correct exposure. This research aims to correct this gap in art history and to outline a chronology of its invention, including the scientific foundation that enabled the development of lightquantifying instruments, photographic precedents and the development of the exposure meter up to the first instance of its modern configuration. This requires an instrument capable of evaluating exposure based on objective parameters, which can measure both incident and reflected light, includes a hemispheric diffuser that enables us to expose three-dimensional objects and is light enough to allow its use outside a laboratory.