directed by Ron Maxwell, Turner Home Entertainment, 254 mins., $95.98 . CODE: BAT-10

The most scrupulous reconstruction of a single battle ever committed to film is now available on videocassette, and although the small screen inevitably diminishes the scope and impact of the spectacle, it does nothing to detract from Martin Sheen’s very interesting portrayal of Robert E. Lee. This is not a man you would want to disappoint, and the scene in which Lee quietly interrogates his high lieutenants about why they failed to take the Union position on Cemetery Hill at the end of the first day’s fighting is just about as scary as the one in which Longstreet’s doomed brigades start off toward Cemetery Ridge two calamitous days later. Jeff Daniels plays Lee’s counterpart—or, rather, the officer Michael Shaara made his counterpart in The Killer Angels , the splendid novel from which the film was drawn: Col. Joshua Lawrence Chamberlain, whose 20th Maine held the extreme left of the Union Line on the second day, thereby saving the Army of the Potomac and possibly the federal Union. Earlier in the film Daniels does a very creditable job of delivering that most difficult of soliloquies, a what-we’re-fighting-for speech. Gettysburg is a serious and careful attempt to put history on film, and if you haven’t seen it, you should.