Albedo

For this monographic exhibition, Hervé Charles has chosen an enigmatic title: albedo, a Latin word meaning "whiteness". In the Middle Ages, the term was used by alchemists to refer to the second stage of the Magnum Opus, the Great Work aimed at transmuting impure materials into gold – the most noble of metals.

In the 18th century, it was adopted into French as albédo by the mathematician and astronomer Johann Heinrich Lambert (1728–1777) to describe the reflective power of a surface. Simply put: the lighter and more reflective a surface (like fresh snow), the higher its albedo. Conversely, a dark surface (like cooled lava) has a low albedo.

This phenomenon is a crucial factor in climate regulation, as albedo influences how much energy the Earth absorbs: by reflecting a significant portion of solar radiation back into space, a bright surface helps to lower ambient temperatures and thus limit atmospheric warming. In contrast, a dark surface absorbs heat, contributing to a rise in temperatures.

The title Albedo thus encapsulates both the artist’s environmental concerns and his reflections on his chosen medium: photography. Light is, after all, the raw material of photography, whether in its imprint on photosensitive film (analogue cameras) or electronic pixels (digital cameras). Hervé Charles uses both techniques to capture fragments of natural landscapes. Indeed, the Earth – with all its upheavals and transformations – has been central to his work since his earliest creations in the 1990s.