Claude Félix Abel Niépce de Saint-Victor (26 July 1805, Saint-Cyr, Saône-et-Loire – 7 April 1870, Paris) was a French photographic inventor.

At his laboratory near Paris, Saint-Victor worked on the fixation of natural photographic colour as well as the perfection of his cousin's heliographing process for photomechanical printing.

In 1857, long before Henri Becquerel's discovery of radioactivity, Saint-Victor observed that, even in complete darkness, certain salts could expose photographic emulsions.

Niépce's superior, Michel Eugène Chevreul, recognized the phenomenon as a fundamental discovery, pointing out that uranium salts retained their power to expose photographic plates even after six months in the dark.

[6] In 1861, Niépce stated that uranium salts emitted some sort of radiation that was invisible to the human eye:Original : " … cette activité persistante … ne peut mème pas être de la phosphorescence, car elle ne durerait pas si longtemps, d'après les expériences de M. Edmond Becquerel; il est donc plus probable que c'est un rayonnement invisible à nos yeux, comme le croit M. Léon Foucault, … .