SAN FRANCISCO  It was a dream come true, straight out of “Antiques Roadshow.” In 2000 Rick Norsigian, a painter in a school maintenance department, bought a box of photo negatives at a garage sale in Fresno, Calif., for $45. Last month, a decade later, he stood in a Beverly Hills art gallery to announce that a team of experts had concluded “beyond a reasonable doubt” that Ansel Adams had taken the pictures.

The gallery’s owner, David W. Streets, appraised the value of the 65 images, which the experts called “the lost negatives,” at $200 million, and the incident made news around the world.

But a fairy-tale ending is eluding Mr. Norsigian. A day after the announcement, Matthew Adams, a grandson of the photographer, disputed the finding, questioned the credentials of the experts and went so far as to call the whole business a “scam.”

A few days after that, an Oakland woman, Marian Walton, announced that she had a photo that was identical to one of the negatives. It had been taken, she said, not by Adams, the famous outdoors photographer, but by an uncle of hers, Earl Brooks.