December 11, 2013
Photographer: Marco Fleury
Summary Authors: Marco Fleury; Jim Foster
The photo above shows astounding shadows brooding above the Graian Alps in southeastern France. It's obvious that these shadows simulate the jagged ridge-line, but what caused them to loom so high in the sky? A clue is the position of the Sun -- directly behind the ridge. It's likely that mist or dust formed a layer, or multiple layers, between the camera, situated near the village of Chamonix, and the mountain. Since the camera is closer to the mist than to the approximately 12,000 ft (3,660 m) mountain itself, the shadows are greatly expanded. This phenomenon has nothing to do with any sort of camera artifact; rather it's a matter of perspective. Since the mist layer is physically closer, the angle it makes (with the camera lens as the vertex) is larger than the angle made by the ridge. The layer is too dim to be visually detected here. Photo taken in 1973.