Background: Whiteley, a retired photographer for the Georgia Department of Archives, collects 19th century photographs. He owns dozens of daguerreotypes, a photographic process perfected by French chemist Louis Daguerre in 1839. Whiteley's collection is primarily portraits, while his wife collects 19th century photographs of cats. Between the two of them, they have about 2,000 old photos in a beautifully furnished, climate-controlled and windowless basement room. Whiteley has so many rare photos that his room has become a destination for major collectors, including rock musician Graham Nash of Crosby, Stills & Nash fame. "He has been here a couple of times," Whiteley says. "He calls it 'the Room.' "

"This collection is the result of 30 years of relentless pursuit," Whiteley says. He buys photos from dealers, antique stores and at auction.

Joey Ivansco / Staff (ENLARGE)

George Whiteley stands by his American Ivorytype, circa 1855. The woman in the luminous portrait is believed to be Frederick Wenderoth's wife.

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Whiteley was a consultant to the Hallmark Photographic Collection, among the finest private collections of photography, which is now in the Nelson-Atkins Museum of Art in Kansas City, Mo. He also is a conservator and dealer of old photographs.

Favorite piece: An American Ivorytype portrait, circa 1855. It measures 17-by-21 inches and is one of only two existing photos of that size using the obscure and labor-intensive American Ivorytype process. The other example is in the George Eastman House collection in Rochester, N.Y.

Frederick Wenderoth invented the American Ivorytype, which involved making a print from a wet plate negative, then dipping the print into molten white beeswax before applying it a piece of glass. The finished product was colored with oils and mounted on ivory-colored paper with spacers to give it depth. The woman in the portrait is believed to be Wenderoth's wife.

Why he likes it: The photo has a luminous

3-D quality created by the wax on the print and the unusual backing. Also, Whiteley says, "it's the rarest thing in a room of rare things."

My Favorite Piece is a way to let Atlantans talk about the best-loved works in their collections. If you have a suggestion, email Kirsten Tagami at ktagami@ajc.com.