To some critics of the response effort by BP and the government, instances of news media being kept at bay are just another example of a broader problem of officials’ filtering what images of the spill the public sees.

Scientists, too, have complained about the trickle of information that has emerged from BP and government sources. Three weeks passed, for instance, from the time the Deepwater Horizon oil rig exploded on April 20 and the first images of oil gushing from an underwater pipe were released by BP.

“I think they’ve been trying to limit access,” said Representative Edward J. Markey, a Democrat from Massachusetts who fought BP to release more video from the underwater rovers that have been filming the oil-spewing pipe. “It is a company that was not used to transparency. It was not used to having public scrutiny of what it did.”

Officials at BP and the government entities coordinating the response said instances of denying news media access have been anomalies, and they pointed out that the company and the government have gone to great lengths to accommodate the hundreds of journalists who have traveled to the gulf to cover the story. The F.A.A., responding to criticism following the incident with Southern Seaplane, has revised its flight restrictions over the gulf to allow for news media flights on a case-by-case basis.

“Our general approach throughout this response, which is controlled by the Unified Command and is the largest ever to an oil spill,” said David H. Nicholas, a BP spokesman, “has been to allow as much access as possible to media and other parties without compromising the work we are engaged on or the safety of those to whom we give access.”