Robb Kendrick with a wet-plate camera in British Columbia.

By RANDY KENNEDY

For more than 20 years the photographer Robb Kendrick has traveled around the United States, Canada and northern Mexico visiting places where people still herd cattle for a living. Such areas, where development has been slow and cellphones are too far from the nearest tower to work, are increasingly rare.
Mr. Kendrick, a longtime contributor to National Geographic, fits in well in these places not only because he is a sixth-generation Texan, raised in ranch country in the state’s northern region, but also because of the unusual method of photography he favors. It was patented and popularized at a time when the idea of the American cowboy was itself just being created.
He doesn’t need batteries or memory cards or even film for his pictures. Mostly he just needs time and lots of patience. And as he labors, moving methodically from beneath the hood of his wooden box camera to a portable field darkroom, bearing wet iron plates that he has painstakingly prepared, he thinks of himself not as simply making pictures but also as taking part in the world of the cowboys who are the subjects of his otherworldly tintype portraits.
“The tendency of cowboys is to think of photographers as very demanding, highmaintenance people,” Mr. Kendrick said. “And in the end I think they really respect the fact that I have to work for these pictures. They respect any kind of honest hard work.”
Mr. Kendrick, 45, belongs to a growing group of commercial and art photographers - including gallery stars like Sally Mann and Chuck Close - who have retreated in recent years from the ease and exactitude of the digital age and taken up the difficult, ethereal techniques of early photography, including the ambrotype (in which a unique image is created on a glass plate), daguerreotype (on polished silver) and tintype (usually on tin-plated iron ).
The latest result of Mr. Kendrick’s twin obsessions - with tintypes and the men who continue to make their livings on horseback - is “Still: Cowboys at the Start of the Twenty-First Century,” a new collection of 148 tintype portraits published by the University of Texas Press.
The pictures - made by exposing and developing the metal plates after they have been coated with a light-sensitive solution of silver nitrate - are a kind of ideal meeting of subject and style. Many of the cowboys yearn to have been born in the 19th century. And the tintypes, with their sepia tones, blurred peripheries and ghostly aura, take the cowboys back to the era when such photographs were taken by traveling commercial photographers. Mr. Kendrick’s impulses may be more nostalgic and sociological than artistic, but the best of the pictures have a timeless power .
For the new book, and an earlier one, “Revealing Character,” published in 2005, Mr. Kendrick estimates conservatively that he has covered more than 64,000 kilometers of often lonesome road in his pickup truck and visited more than 60 ranches, towing a trailer that he uses as a darkroom.
(The most recent version of this mobile darkroom, specially made for him by a Mennonite company in Indiana, is as high-tech as his wooden cameras are primitive; it has an iPod docking station, climate control and stainless steel countertops.)
Mr. Kendrick has long been drawn to cowboys as subjects, in part because he grew up around so many in Hereford, Texas, but also because he finds the endurance of their culture and mythology - more than a hundred years after the last great cattle drives - to be as fascinating as that of other groups he has photographed, like Sherpas in the Himalayas or the Tarahumara Indians of northern Mexico.
“Many cultures threatened by so-called progress can lose much in a matter of one or two generations,” he writes in the new book. “But cowboys - actual working cowboys, in all their manifestations - proudly and determinedly endure.”