The tintype is set to be auctioned Saturday evening at Brian Lebel's 22nd Annual Old West Show & Auction. Organizers expect it could fetch between $300,000 and $400,000.
Auction spokeswoman Melissa McCracken said she expects private collectors as well as some museums to enter the bidding. She wouldn't comment on who is interested in buying.
The tintype is believed to have been taken in 1879 or 1880 in Fort Sumner, N.M. It shows the outlaw dressed in a rumpled hat and layers of clothes, including a bulky sweater. He's standing with one hand resting on a Winchester carbine on his right side and a Colt revolver holstered on his left side.
Tintypes were an early form of photography that used metal plates. They are reverse images, and the Billy the Kid tintype led to the mistaken belief that Billy the Kid was a lefty. The myth inspired the 1958 movie "The Left Handed Gun", starring Paul Newman as Billy.
Billy the Kid gave the image to a friend, Dan Dedrick, and the tintype has been owned by his descendants, the Upham family, ever since. It has only been publicly displayed during the 1980s at a museum in Lincoln County, N.M.
McCracken said it's recognizable around the world as a classic image of the Old West.
"There's only one photo of Billy the Kid, and I think that's why it captivates people's imagination," she said.
The auctioneer will set the opening bid, and bids will be taken live in the 400-seat hall as well as over the phone.
The tintype was to be sold along with more than 400 other Western-themed items, including documents from Buffalo Bill's aborted divorce, Native American antiquities, and a painting from Andy Warhol's "Cowboys and Indians" series depicting a Navajo woman with a baby on her back.
(Copyright 2011 by The Associated Press. All Rights Reserved.)