Journalists covering crime and other stories in Oakland, Calif., are being robbed of expensive cameras, sometimes at gunpoint. In less than a year, every major television news station in the Bay Area has been a victim, some more than once. One newspaper photographer has lost five cameras. In the most brazen episode, a group of men punched a KPIX-TV cameraman last November while he was filming at midday in front of an Oakland high school. The robbers fled with his camera while it was still recording. Viewers saw the reporter sign off and then an inexplicably wobbly image.