The Portuguese Center of Photography has several stereoscopic collections and archives at its disposal. The
archives of Aurélio da Paz dos Reis, Alberto Marçal Brandão and César Moura Brás are some examples of the
use and exploration of this technique. Other international authors, like Adolphe Block, are represented in
collections such as the Coleção Nacional de Fotografia (International Photography Collection), Alcídia e Luís
Viegas Belchior or António Pedro Vicente. The perception of depth using artificial form made this technique
one of the most common means in the society of the 1920s and 1930s.