"To create images that are not boring, you could concentrate on the purpose to take films and not the purpose to be safe on your skis," Menna said. He added that any potential tendency of helmet cams leading to more risk-taking and accidents was not yet reflected in official statistics.
A definitive evaluation of Schumacher's speed could still be established by Quincy's investigation, which the prosecutor said could be completed within several weeks though he gave no deadline.
Quincy said the inquiry, which is standard after any major skiing accident, was intended to discover what happened, not necessarily fix blame.
Without specifying, he said authorities plan to interview more witnesses. Schumacher's 14-year-old son Mick was also skiing in their small group.
Quincy said experts would be called in to review the Schumacher camera footage, though the exact reason why the German racing driver chose to ski off a groomed track into a small, rock-strewn area of open ground could remain unclear.
"If we receive other testimony that would establish another motive than skiing in this powder and off piste snow, including to rescue someone, but I do not have these elements so it is difficult for me to speak about it," the prosecutor said.
Schumacher's doctors have consistently refused to predict when he might be able to add his own words to the images captured on camera.
In the meantime, the popularity of the helmet cameras seems likely to increase.
Users need to additionally spend around $40 to fix cameras on a strap which wraps around a helmet, or mounting to attach to a ski pole or handlebars. Video editing software is available free to download.
Endorsement from top athletes and increased exposure from capturing adventure sports events such as the X Games also are pushing cameras as a must-have gadget.
Injury lawyer Edouard Bourgin, who specializes in skiing accident cases, said use of video cameras on ski slopes is just part of the technological revolution of recent years — allowing lawyers to use evidence from video footage, text messages or online postings for case files — especially in criminal cases.
Bourgoin said he was unaware whether helmet camera video had ever been used as part of an Alpine skiing case, but that he "doubted the Schumacher accident was a first."
"It's clear that a skier who doesn't go the proper speed or goes too fast can see his right to compensation reduced depending on his or her own fault," Bourgin said from his office in Grenoble, where Schumacher has been hospitalized.
Associated Press correspondents Deborah Gouffran in Albertville and Jamey Keaten in Paris contributed.