Mayor Marion Barry sat in the harsh glare of television lights at a press conference last Thursday and told the world he was unconcerned about the media coverage he gets.

"You newspaper people spend more time on my image than I do," Barry said, with beads of sweat glistening on his forehead. "When I go to sleep at night I'm not thinking about the media. I'm thinking about housing, employment . . ." and he rattled off a list of issues that he said leave him little time to ponder his public image.

Barry, who enjoyed excellent press relations as school board president and City Council member and who promised an open administration when he ran for mayor, has become less and less accessible to reporters in recent weeks. He also seems determined to establish controls over the flow of information from city government.

There is certain logic to Barry's new reticence. Aides to the mayor, as well as media specialists who frequently advise him on public relations, say Barry has been stung by criticism of the administration's handling of the city's worsening budget crisis and repeated reports of inefficiency by the city bureaucracy.

"When you have serious problems, it may not be the time to be yakking with the press corps," said Ivanhoe Donaldson, Barry's general assistant.

"I think he's beginning to realize that there are so many areas for the press to poke in and do negative stories," said Dwight S. Cropp, executive secretary of the mayor's office. "I can do 10 positive things, but there are so many negative things out there, the positive things never show up."

Within the past several months, news sotries have detailed not only the administration's problems in trying to get a handle on the budget, but also a host of other bureaucratic snafus ranging from failure to pursue parking offenders who pay with bad checks to lax supervision of the city's foster care program.

The press reports have seemed to take an emotional toll as well, observers said.

Last Wednesday, Barry shut down his press office. The administration maintains that technically the office is still open, but press spokesman Kwane Holman offered his resignation after reportedly being told he would have to take a demotion to fit into a new, centralized press information structure. Holman's secretary was transferred to the mayor's private staff.

Barry has adopted a new policy of refusing to talk to reporters he encounters in the hallways of the District Building -- formerly a common practice -- unless they go through channels to set up a formal interview or ask their questions at a press conference.

Barry has also sought to effectively ban reporters from the inner corrider that leads to his own office. The hallway is lined with the offices of aides, and reporters previously had free access. But when he spotted a reporter in the corridor last week, Barry snapped, "Get out of the hallway, you're not supposed to be in here."

Said Donaldson of the incident, where he did not witness, "Maybe he [Barry] was in a bad mood. It becomes a point of frustration when the mayor is walking down the hallway and has to answer 50 to 100 questions."

According to advisers, Barry has also been stung by criticism of some of his own actions -- like accepting and at first concealing a cut-rate mortgage on his home that was offered because his wife Effi is on the board of directors of the lending institution. He also accepted and later declined a free trip to Paris in the midst of the budget crisis. And Barry, a former activist, once told some pickets protesting his proposed budget cuts to "Go to hell."

Some members of an ad hoc group of media specialists who advise the mayor on his image say these incidents cropped up partically because of Barry's reluctance to take advise. Another factor, they say, is his failure to adaquately define his image he wants to project as mayor of the nations's capital.

"Is it Marion the militant?" asked one of the public relations professionals who asked not to be named. "Is it Marion the survivor? Is it the tempermenal Marion who shoots from the hip, duels with the City Council and shoots it out with Congress? Or is it Marion the elder statesman?"

The advisor said that Barry was warned not to take the cut-rate mortgage and not even consider the Paris trip.

"The fundamental problem he has now is learning to accept good advice," the media specialist said. "Sometimes he can be stubborn. We tell him, 'Mr. Mayor, you really shouldn't do this.' In the meantime, he's getting clobbered."

Some of the mayor's aides have taken to blaming reporters for concentrating on Barry's gaffes. "My impression is that you have your marching orders to put the mayor on the hot seat," Cropp told a reporter. "I think all of you are out to burn him."

But the media specialists say they are advising Barry to begin taking a lower profile. "One of his first mistakes was his attitude toward the media," one said. "He felt he always had to be doing something to get favorable coverage. Well, he's mayor and he's not in the middle of a campaign.

"There's no need to have stories about him in the papers every day."