It was a horrifying image that stunned the nation - President John F. Kennedy, cut down by an assassin's bullet. Now, in an era when even the smallest Kennedy trinkets fetch fortunes, the 26-second home video of the shooting has pitted the federal government against the cameraman's family in a battle over its worth.

Abraham Zapruder's family, which owns the original film and the copyright, wants $18.5 million for the film he shot Nov. 22, 1963, in Dallas. The Justice Department has reportedly offered $750,000 while indicating the upper range might go as high as $3 million."We simply are trying to make sure that the taxpayers are not paying too much for the tape," Justice Department spokeswoman Chris Watney said Saturday. "We have had discussions, and we will continue to have discussions."

The original film, which the family deposited in a National Archives vault in the 1970s, is considered vital evidence in the investigation of Kennedy's assassination. Zapruder died in 1970, and over the years the family has allowed noncommercial users such as teachers and students to use the film for free but has charged fees for commercial uses such as in Oliver Stone's movie, "JFK."

In 1992, Congress created the Assassination Records Review Board to amass all relevant evidence in the Kennedy case. The board declared in April 1997 that the film belongs to the federal government.

"If there is one assassination document above all assassination documents, it is the Zapruder film," review board member Anna Nelson said. "What we frankly had hoped was that the Zapruders would . . . give the film to the American people. It would be a gesture."

Experts say technology someday could be developed that would yield new information about the assassination from the film's frenetic, blurred images.