IF YOU'VE been putting off seeing Shoah, go now. This is the final weekend in Washington before Claude Lanzmann's 91/2-hour landmark documentary on the Holocaust closes Thursday at Georgetown's Key Theater. There are only a handful of copies of the French-made film in the U.S, and the Key's copy is slated to open in another city. The film is shown in two parts, Part 1 on Wednesday through Saturday; and Part II, Sunday through Tuesday. Tickets are $10 per part. Call 965- 4401 for screen times.

The departure of "Shoah" clears the way for the much-heralded 160-minute Japanese epic, Ran, which opens at two screens at the Key on January 24.

The Imax Film Festival continues at the Air and Space Museum's Langley Theater with three shorts screening through January 26. On almost any night of the week beginning at 7:15, you can see The Universe -- We Are Born of Stars, an 11-minute trip through the five-billion-year history of the solar system; Skyward, a 24-minute story of man's fascination with flight; and Freedom to Move, an 18- minute look at the far corners of the world. Cost is $3.75 for adults, $2.50 for children.

Only special programs such as Friday evening's ongoing "Comet Tales" series will interupt the Imax schedule. This Friday's Comet Tales feature is the 1980 made-for-TV movie Fire in the Sky, starring Richard Crenna. It's free and begins at 7:30.

And remember, To Fly and The Dream Is Alive are shown every day in the five-story- tall Langley Theater. Those films are $1.50 for adults, 75 cents for children, students and seniors. For a schedule, call 357-1686 or 357- 2700.

Paul Wagner, winner last year of a Best Short Documentary Oscar for The Stone Carvers, will again offer a seminar on "How to Start a Career in Independent Film Making." The 21/2-hour program, offered Tuesday at 7 p.m. through Open University, explains the step-by-step process of film production. The class is limited to 60 students and costs $24. Call 966-9606 to register.

Then, on Thursday evening at 8, Gene Miller, a 15-year veteran in television production, begins his four-part class in Television Commercial Production at the Open University. The two-hour classes discuss writing, planning, videotaping and editing 3/4-inch professional quality tape. Cost is $45; the materials fee is $15. The remaining three classes will be held January 30, and February 6 and 13. Miller will begin another four-part commercial production class on March 13. Again, call 966- 9606 to sign up.

First Class Inc. is sponsoring an evening at the movies with film programmer and critic Eddie Cockrell on January 24. Cockrell will take the class to Twice in a Lifetime, followed by a critiquing session. Cost is $15 and includes the movie ticket. To register, call 797- 5102.

If you're looking for pictures with a lot of depth, try Friday night's double feature at the U.S. Department of Commerce auditorium. Beginning at 7:30, National Geographic Society staff photographer Emory Kristof unveils his rare slides of the Titanic, which has been lying 13,000 feet below the North Atlantic since 1912.

The program also features photographer/diver Gary Gentile's slides taken inside the Andrea Doria. The Italian luxury liner, which sank in 240 feet of water in July 1956 after colliding with a Swedish liner off Nantucket Island, was loaded with jewelry and fine imports. Gentile's exhibit includes the ship's bell, which he recovered this summer. Tickets are $5; proceeds benefit the National Sudden Infant Death Syndrome (SIDS) Foundation. The auditorium is at 14th and Constitution Avenue NW. Call 301/647-1885.

Actor Michael Nouri, best remembered as the handsome construction company boss who caught Jennifer Beals' eye in Flashdance, will spend most of next week on local television shows promoting his latest film, The Image Maker.

The political thriller, produced by Hal and Marilyn Weiner's Georgetown-based Screenscope company, will have its world premiere next Friday at the West End Circle. Nouri plays the lead character who seeks revenge against the White House bad guys responsible for his ouster as media consultant to the president. Between stops on shows such as Panorama, PM Magazine, the Carol Randolph Show and Live at Five, he'll get his first taste of a real daily White House press briefing on Thursday at noon.

Atlantic Entertainment Group will launch the Clubhouse Pictures Family Network this Friday with Hey There, It's Yogi Bear. The theater network is over 1,000 houses strong nationwide and plans to screen quality G-Rated movies on a regular basis. Each film will be the main attraction during opening week and will then be shown as a matinee for at least three more weeks. Many of the movies will be new releases.

Clubhouse says it will guarantee moviegoers a minimum four-week run at a theater. About 15 Washington area theaters, including the Tenley Circle theater, have signed on with Clubhouse.

"If we don't develop a kid market now, they'll turn to home video and we'll lose them forever," says one Atlantic executive in explaining the new network.

Additional features scheduled are The Adventures of Mark Twain, opening February 14 and The Gobots Movie, American Rabbit, and Heathcliff's First Movie in the following months.

The Variety Club of Greater Washington has elected Glenn Abrams, the local branch manager for Columbia Pictures, as the organization's chief barker (president) for 1986. He replaces Elias Savada, of the American Film Institute and the Washington-based Motion Picture Information Service, who takes over as chairman of the board. Other board members are Ted Pedas, owner of the Circle Theaters; Tom Perakos, chief executive officer of Circle Theaters; Peter Carney, owner and operator of Cinema 'n' Draft House; Ross Wheeler, president of Wheeler Film Company; and Jerome Sandy, a branch manager for Orion Pictures.

Now in its 52nd year in Washington, the Variety Club uses the talents of the entertainment business to raise money for the Myoelectric Limb Bank and Children's Center.

SHORT SUBJECTS -- The National Archives' free "America Lives" series offers The Highly Exalted (1985), Friday at noon in the fifth-floor theater. The 50-minute film trails one of the last remaining horsedrawn chuckwagons in America and uses spectacular Nevada scenery.

The American Film Institute Theater screens the restored version of Orson Welles' Touch of Evil on Friday at 6:30 . . . The continuing "Down Under Festival" at the Biograph Theater in Georgetown screens Peter Weir's highly successful 1983 adventure The Year of Living Dangerously, starring Mel Gibson, Sigourney Weaver and Linda Hunt, along with the 1981 hit Breaker Morant, Friday through Monday. Call 333-2696 for showtimes.

The Alexandria campus of Northern Virginia Community College begins its free "Film Watchers Series" on Friday evening with the 1979 Don Giovanni. Showtime is 8 p.m. in the Bisdorf Building, Room 110. The public is invited. Call 846-6207 . . . On Tuesday at 7:30, the Arlington County Library continues its program of "Winter Films for Adults" with George Washington Carver (1984), Great American -- Martin Luther King Jr. (1985), I Had A Dream (1968); and Paul Robeson: Tribute to an Artist. It's all free, at 1015 North Quincy Street. Call 525-3086.

Alfred Hitchcock's thriller Psycho screens free at noon on Wednesday in the American History Museum's Carmichael Auditorium . . . Also on Wednesday, the Smithsonian Resident Associate Program's Festival of Indian Films continues in Carmichael at 7:30 p.m. with the 180-minute Ardh Satya. The film is presented with English subtitles. Cost is $4 for resident associates, $6.50 for nonmembers. Call 357-3030 for reservations.

The Renwick Gallery will screen Children of the Mist, a New Zealand short feature in conjunction with its "Treasures of the Land" exhibition, on Thursday at 11, 12:15 and 1:30. Call 357-2700 . . . The Gaithersburg Regional Library's "Night Flight" series offers Ballad of a Soldier, in Russian with English subtitles, on Thursday at 7 at 18330 Montgomery Village Avenue.