Whatever the process, chemical or electronic (commonly called digital), the emulation of luminosity is all about light and electrons. It is the light that pumps the electrons from a level (electronic band) to the next in both, a photosensitive semiconductor or a silver bromide crystal. Once the light is absorbed what happens next is quite different for chemical and electronic photography, but the primary step and light-trapping device follows essentially the same principles in both techniques. To a certain point the process of light detection is not much unlike that of vision and the photographic simulation of luminosity is quite successful. The same cannot be said about color. The photographic color relies on optical filters, which is a quite different “technology” from that inbuilt in our retina. As a consequence the reproduction of simulated colors hardly fits our perception.
CV | Eurico Melo
Eurico Melo, born in 1949, obtained a Ph.D. degree in Chemical-Physics at the Instituto Superior Técnico where he was an Assistant Professor until retirement. Group leader of the Micro-Heterogeneous systems Laboratory at Instituto de Tecnologia Química e Biológica – UNL, his research comprises the study of the structure of bilayers and other lipid assemblies of biological relevance, and the chemical equilibrium and kinetics in dimensionally restrained biological media.
Is interest for photography is more aesthetic than technical, but the background in physical-chemistry and spectroscopy provides the necessary tools to better understand the photographic process, being it the conventional methods based on chemistry or those of electronic photography.