A top writer, a top director, a top producer, yes--but more than ever, today's movies must have a bottom line. Representatives from 37 state film offices heard that message for the second day in a row yesterday, this time from John Frankenheimer, the director of "Black Sunday," "Seven Days in May," "The Train," "Exorcist II" and many other feature films.

"It was really the Florida film commission that made 'Black Sunday' possible at all," Frankenheimer said. "Since it was the story of a blimp crashing into the Super Bowl, we had to be able to shoot by early February.

"But as late as November, Paramount was still saying they wouldn't make the picture unless we cut $1.5 million from the budget. Well, we had $2 million budgeted for extras alone, in order to fill up the Orange Bowl. So the Florida commission made this offer: If I would direct a United Way film for them, and if Robert Shaw would narrate it, they would contribute 75,000 volunteers for three weeks' shooting.

"It worked. When I made 'The Train,' we used 800 extras as the whole German Army. It was easy because you could move them around. But for 'Grand Prix,' we needed 8,000 people to just stand at the hairpin turn in Monte Carlo. So we announced a raffle on Radio Nice, and we got the crowd that way. We only needed them to stand there for 2 1/2 seconds, which was how long it took the cars to zoom by."

The film commissioners, in the third day of "Cineposium '82" at the Capitol Hill Holiday Inn, are trying to learn new tricks for luring moviemakers to their locales.

The reason is that movies are lucrative visitors: One major production brings between $2 and $10 million to a state. New York City alone was the site of 76 movies and 47 television programs last year, and a reported $750 million changed hands. The District of Columbia was host to crews from "Reds," "First Monday in October," "The Amateur" and the television autobiographical drama "Will."

The first visit to a state, Frankenheimer said, is usually from a producer, writer and director working on a "development deal," and seeking scenics, facilities and cooperation.

"When we come in you might think: Boy, these guys are relaxed--they have a sense of humor, they're cracking jokes," Frankenheimer said. "That ends the moment the film crew of 150 people arrives. After that it's deadly serious. We'll be spending an average of $12,000 an hour, and nothing is going to throw us off schedule."

The host state or city will be expected to know its vintage car clubs. "Because that's where we get the cars for period movies. Make sure you know where we can get period clothes. Make sure the banks are open for us. We'll need to take over a motel, a cheap place to eat. We need emergency transportation. And we will stop at nothing. Remember, it's $12,000 an hour."

Frankenheimer, who bears an accidental resemblance, both in posture and tone of speech, to the director portrayed by Robert Klein in the Burt Reynolds' movie "Hooper" (that character got punched in the nose, but Frankenheimer is widely admired), then told a "Seven Days in May" story.

Because of the antimilitary nature of that doomsday story, "the Pentagon absolutely forbade us to shoot there," he said. "But we had to get one scene. So we arrived in town in the middle of the night. We rented a station wagon for the cameras and a limo for Robert Duvall. He put on his general's uniform. At dawn, we pulled into the Pentagon lot. We quick set up the camera and shot Duvall walking into the building. Then we changed lenses, while Robert waited inside in his general's uniform. Then we gave him the signal and he walked out toward the camera. As he was walking out, a Marine Corps colonel saluted him."

That was a case where publicity complicated the shooting schedule. That also can happen, he said, if word gets out that a film is being made in a public place.

"We spend most of our time getting people away from the cameras, not in front of them," Frankenheimer said. "When I was shooting 'Seconds,' we had a scene in Grand Central Terminal in New York starring Rock Hudson, and our plans got in the papers. So we set up three different cameras at the station. At one camera, the writer of the picture was acting like a director, shouting and waving, and a crowd gathered. At another camera, we had a Playboy bunny, and she drew a crowd. Then we had the real camera, and nobody even noticed Rock Hudson."

In the best of worlds, the state or city film commission will make these little problems disappear before they even happen. But this is an imperfect world.

"One time I was looking for the perfect rundown bar, and I finally found one to shoot. It was great. Authentic junk all over the walls, drunks passed out at the bar, the whole thing. It's hard to get that authenticity, so we always like to 'steal' shots from reality. Well, when we came back three weeks later with the film crew, the whole place had been repainted and done over to look like Better Homes and Gardens. They said they wanted the bar to look good, because it was going to be in a movie."