THE BIG SLEEP - ABC DRIVE-IN, ACADEMY, ANDREWS, ARLINGTON, AVALON 2, FAIR CITY MALL, LANDOVER MALL, LAUREL TOWN CENTER, ROTH'S SEVEN LOCKS, ROTH'STYSONS CORINER AND WHEATON PLAZA. The makers of the second film version of "The Big Sleep," a Raymond Chandler detective story first filmed in 1946, own up to only "one challenging change." They are not counting substituting Robert MItchum for Humphrey Bogart, Sarah Miles for Lauren Bacall and Michael Winner as (among other thing) the writer of the screenplay for William Faulkner, which are changes that some may notice.

The change is the locale, from Los Angeles to LOndon, an inspiration at which Chandler "would have been delighted," they claim, because he had lived in London himself - but presumably never would have been able to think of using it.

What makes this change significant is its contribution to making the film incomprhensible.All that hinted-at homosexuality, drug addiction and pornography may have been hard to comprehend in the first version, made in days when Hollywood scarcely acknowledged such doings, but in London of the "70s, among the scruffier members of cafe society, why would anyone get upset over such trifles? Could a drug-filled, sex-obsessed, murderous heiress be blackmailed with pornographic pictures of herself? Why, the publication of them would be the making of her. IF her father had hired a public-rlations man to promote her, instead of a detective to protect her, that might have made sense.

Another, unheralded change is its lust for luxury. The most unlikely film genres - this detective movie, the horror picture "The Fury" - are suddenly filled with Fifth Avenue stataus-symbol clothes, watches, furniture, sheets, all dwelt upon with great attention.

But instead of making the wearers seem more serious, as if they were people who really know their way around the modern world, it gives them the look of mannequins in a department-store window, arranged to play at rigid violence in the hope of momentarily cataching the attention of passersby who are, say, Raymond Chandler fans, or Humphrey Bogart fans.