South Africa's 4-month-old ban on television coverage of many racial trouble spots has muted coverage of the conflict for U.S. viewers and highlighted television's inherent problem of telling a story without being able to show it, according to network executives.

"The sad fact is that" the South Africans have "mostly succeeded in what they wanted to do," said ABC News vice president and Washington bureau chief George Watson.

"We have done 'stand-ups' " with a correspondent standing before the camera and telling the story "and used graphics and tried to get around this. But the truth is that it doesn't make good television," he said.

Representatives of the major networks said last week that they are increasingly committed to covering the South Africa story since the government forbade use of cameras in key areas, starting Nov. 2.

"But it won't be easy," CBS Evening News anchor Dan Rather said. "We're having one hell of a time trying to make it accessible and interesting, but we are determined to continue to report the reality, not the unreality that the government would like us to report."

During recent riots in the township of Alexandra, for example, some crews working for U.S. networks perched on hills in surrounding white areas, using telephoto lenses to photograph trouble involving blacks.

Although grainy by American television standards, their footage showed conflict, and South African authorities expanded the ban a day later to include an area that put Alexandra beyond range of television's longest lenses.

Rather responded on the air that day by showing a chart of the area purged of television journalists, adding a new twist to the almost daily explanation by American anchors about why they have no pictures of the racial troubles in the news.

Most television executives said such explanations begin to lose their luster with viewers accustomed to seeing the world's problems in close-up and in color.

"You can't keep bringing your professional problems to the American public," said Richard Kaplan, executive producer of ABC News' "Nightline." "It's worth mentioning because people have a right to know, but I don't think that every time something happens you can put up a map and show where the cameras were. It just doesn't work."

In recent weeks, two networks have used another tactic. They have filmed disturbances in areas where cameras are allowed and used those videotapes on news programs to show incidents "similar" to ones ruled off-limits.

NBC News has shown footage of rioting from a township called Krugersdorf, where correspondent John Cochran had been filming an encounter between blacks and police several days before Alexandra erupted.

Similarly, "CBS Evening News" recently used videotape from correspondent Allen Pizzey in South Africa in the small black township of Atteridgeville.

The report showed how trouble erupted after a funeral and included the sight of a South African official wielding a stick against a fleeing black man. It also included shots of police spraying blacks protesters with dyed water so those fleeing the confrontation could be tracked easily.

"They think they can sweep all their problems under the rug by shutting off our cameras," said Sam Roberts, CBS news foreign editor. "We don't give up that easy."

Pizzey paid a price his journalistic ingenuity. He was arrested and, while waiting for a CBS lawyer to gain his released, a policeman "harassed" him, Roberts said.

"This policeman -- he must have been 6 feet 4 -- threw a punch, barely missing Pizzey's ear and banging against a steel locker behind him," Roberts said, referring to Pizzey's report to network executives.

Pizzey and his crew were released, Roberts said, but not until after the policeman had threatened to kill him and other officials made photostat copies of his notebooks.

"What the government keeps pumping out is that we have these rules, we're entitled to make these rules and reporters have to obey these rules and, if they do, there is no problem with their coverage," Rather said. "Not true. They systematically have the police harass reporters even when they go by the book."

"What we have not done is a good enough job of reporting that this is systematic harassment with the intention to intimidate," he said.

Many South African officials appear to feel that the ban on cameras is a success.

Several network executives said South African diplomats have told them that, in certain areas, the ban effectively reduced the number of nightly riot pictures on U.S. television. They also suggest that, because the cameras are not present, violence has diminished.

J.H.A. Beukes, South Africa's ambassador to the United States, said at a recent American University forum that, in areas where cameras have been banned, there has been less trouble.

"There has indeed been a reduction, no question about that . . . but what is more important is that there is no way of telling how many more or how much more violence could have occurred if this had not been done," he said.

The suggestion that trouble is caused or aggravated because television cameras are present angers and disturbs many in the television industry.

"Any suggestion that the violence has stopped because there are no television cameras is just not true," said Timothy J. Russert, vice president of NBC News.

"The violence has remained at least as high, and I believe it's higher since the restrictions were imposed," ABC's Watson said. "And I think the motive of the South Afican government . . . is [not] so much to prevent or cool down violence, but it is to prevent the outside world from seeing the violence in the most graphic way."