"Backsliding," an exhibit of photographs by Ralph Lindgren, continues through April 29, Rotunda Gallery, Bethlehem Town Hall, 10 E. Church St., Bethlehem.

An opening reception is 2 - 4 p.m. April 7.

"Backsliding" is composed 41 images, each of which illustrates how digital images can be enhanced by drawing upon aesthetic principles and techniques long admired in many of the more traditional visual media. The sources of inspiration include oil, pastel, acrylic, gouache, ink, engraving, pencil and several multi-media pieces.

Lindgren is a long-time resident of Bethlehem. Following 30 years as a Professor of Philosophy at Lehigh University, he retired in 1995 to peruse his many other interests. These have included volunteer organizations, family genealogy, flower gardening, world travel and, increasingly, photography.

Lindgren has studied online and in person with such notable photographers as Tony Sweet, Brenda Tharp, Deborah Sandidge, Art Wolfe and Rick Holt. During the previous 40 years Ralph perused black and white film photography in his chemical dark room.

The exhibit in the Rotunda Gallery during April places more than three-dozen of the products of this adventure on display.