They are photos of iconic moments but whether certain pictures are true snapshots or false images has overshadowed many of them for decades, reports CBS News correspondent Michelle Miller.

That's the mystery surrounding Robert Capa's "Falling Soldier." An analysis of the photo conducted earlier this year has reignited a decades-long debate about whether the image - supposedly of a man being shot during the Spanish Civil War - was staged. Director of the International Center of Photography, Willis Hartshorn says it's a debate that may never truly be solved.

"You want the negative of the falling soldier, we don't have that negative, you want the negative of the shot after the falling soldier we don't have that negative," Hartshorn says.

Photography historian Philip Gefter says the debate over photo-editing dates back to at least 1860 and a specific photo: When Abraham Lincoln's head was attached to John C. Calhoun's body. Calhoun's pose was thought to be more presidential.

"That's kind of pre-Photoshop, that is what Photoshop is today," Gefter says.