ART

The Portola Art Gallery presents Tafoni - Accentuating the Negative, a collection of images by photographer Alan McGee of Portola Valley. Tafoni is the name given by geologists to the unusual and often beautiful honeycomb formations and shallow caverns created by natural weathering processes in the sandstone outcroppings that occur in the mountains of the San Francisco Bay. This is a phenomenon that occurs only in a few places in the world.

Tafoni afford the intrepid photographer some interesting challenges physically, technically and aesthetically. Physically, because Tafoni occur on precipitous slopes; technically, because of the mostly dark spaces which may require exposures of several minutes; and aesthetically, because the formations while visually interesting often don’t seem to work well in the conventional black and white print.

Alan has photographed these natural forms and presents them as negative images which reverse the tonal values of the conventional print: white and black trade places, and only middle grey remains unchanged. The negative print has its own peculiar form of beauty.

“These negative images of Tafoni, where deep shadows become sources of symbolic light and all sense of spatial orientation is lost, challenge our conventional conceptions of reality,” explains Alan. “These cavernous landscapes become evocative “mindscapes” -- fantasy worlds that invite subjective interpretation. Spaces where tonal values are reversed can become an alternate reality to the viewer.”