Professor, researcher and art critic, he dedicated his career to thinking about technical images - those produced through technological mediations, such as photography, cinema and video, being one of the pioneers in Brazil in the systematic investigation of video as an artistic language. Author of several books, he published O Sujeito na Tela (2007); A Televisão Levada a Sério (2000); Máquina e Imaginário: O Desafio das Poéticas Tecnológicas (1993); A Arte do Vídeo (1988); A Ilusão Espetacular (1984), among other titles and numerous articles in specialized magazines. He is also co-author of Pantanal: A Reinvenção da Telenovela (2008) and Made in Brasil: Três Décadas de Vídeo Brasileiro (2003). He was a member of the Communication and Semiotics department of the Pontifical Catholic University of São Paulo and of Audiovisual department at the University of São Paulo. He was a photography and video critic for the Folha de São Paulo newspaper and curator of several exhibitions, such as Getxoko III (Bilbao), Arco (Madrid), Ícaro (Guatemala). He directed short films in 16 and 35 mm and multimedia works on CD-ROM. He received the National Photography Award from FUNARTE (1995) and the Sergio Motta Award for Art and Technology (2007).