Late-Season Entries Dominate the Oscars - Again. PREVIEWING TOMORROW'S CEREMONIES

ONCE every year, the Academy of Motion Picture Arts and Sciences gives out another round of Oscars. But maybe this should happen twice a year - since the Academy voters apparently have such short memories they can't remember movies they saw before the tail end of the eligibility period. It isn't exactly news that films released early in the year are at a disadvantage when Academy Award voting time comes around. But the current Oscar race, which climaxes in tomorrow night's award ceremony from Los Angeles (ABC-TV, 9 p.m. to conclusion), is a particularly glaring example of the situation:

All five movies nominated for ``best picture'' came out in theaters at the very end of 1988. Even the enormous popularity of ``Who Framed Roger Rabbit'' couldn't overcome the Academy's brief attention span. It received six nominations, but every one of them is in a secondary category like ``best film editing,'' which movie specialists take quite seriously but ordinary fans - and ticket buyers - simply don't care much about.

This isn't to say that ``Rain Man,'' for example, shouldn't have gotten a ``best picture'' nomination. It's no great movie, with its intermittently effective story about a mentally handicapped man and his wheeler-dealer brother learning to love each other during a long automobile trip.

But in a year like 1988, which served up a perilously slim selection of watchable films, it emerged as a reasonably thoughtful and capably crafted offering.

It's also nominated in seven other categories, indicating that several Academy branches (each of which makes nominations in its own field of expertise) found it worthy of professional respect.

Ditto for ``Mississippi Burning,'' which was nominated in the ``best picture'' category and six others. It has generated a lot of controversy with its Hollywoodized story of FBI agents solving the murder of three civil-rights workers in the 1960s. But it works fairly well on a simple good guys-bad guys level, and, despite the shortcomings of its credentials in the race-relations department - it turns the story of the civil-rights movement into a largely all-white affair, for example - at least it has the courage and imagination to put a spotlight on an area of recent American history that's been totally avoided by American movies until now.

The other three ``best-picture'' nominees strike me as more dubious entries in the race. ``The Accidental Tourist'' is a boring male-chauvinist romance with little on its mind but which lucky woman (Kathleen Turner or Geena Davis) hero William Hurt will decide to favor with his affections. ``Dangerous Liaisons'' is two monotonous hours of pretty people standing in pretty rooms and talking about sex. ``Working Girl'' is cute and clever, but it's hardly substantial enough to make a credible contender for best picture of the entire year. Then again, the entire year isn't at issue - considering that all the competitors were released during the Christmas movie season and were fresh in the minds of Academy members when the nominations were decided.

I don't take this imbalance in the Academy Awards too seriously, but that's only because I don't take anything about the Oscars seriously. The whole thing is just a popularity contest, really, and the winners are usually distinguished more by instant entertainment value than cinematic artistry or deep thinking. Still, the nominees enjoy increased business as a result of their Oscar publicity, and tomorrow's winners will pull in even more dollars for the same reason. HOW about films that aren't gaining a single spectator by this route, however? One example - because it wasn't nominated in a single category - is ``The Thin Blue Line,'' the superb Errol Morris documentary about a Texas man falsely convicted of murder, which resulted in his release from prison last week. Why isn't it up for ``best picture,'' or at least ``best documentary,'' or at least ``best score'' (for its Philip Glass music)? It was released way back in the summertime, that's why!

Similar squawks could be raised about ``Tucker: The Man and His Dream,'' the exhilarating Francis Coppola epic about a legendary car manufacturer, and a handful of other films that had the poor judgment to brighten our summer instead of waiting until mid-December and hopping right on Oscar's bandwagon.

Compounding the problem is the fact that ``best picture'' nominees often carry ``best director'' nominations on their coattails. Three of this year's ``best picture'' filmmakers are beneficiaries of this effect: Alan Parker of ``Mississippi Burning,'' Mike Nichols of ``Working Girl,'' and Barry Levinson of ``Rain Man.'' English director Charles Crichton is also nominated (inexplicably) for the comedy ``A Fish Called Wanda,'' and so is Martin Scorsese, who made ``The Last Temptation of Christ.''

Whom would I choose for the Oscar winners? In previous years, I've sometimes made my own list including films that weren't nominated by the Academy itself. But 1988 was such a lean year for good movies that I'll select my preferences from the films that are actually in the race.

My nod for ``best picture'' goes to ``Rain Man'' - not because it's brilliant, but because it's mildly thoughtful, and because Dustin Hoffman gives a boldly obsessive performance that would be too unglamorous for many Hollywood stars to try.

I'll bypass Mr. Hoffman for ``best actor,'' though, and choose Edward James Olmos, a Hispanic actor who was stunningly convincing in ``Stand and Deliver'' as a California math teacher.

It's hard to choose a ``best actress'' winner: I liked Jodie Foster as a rape victim in ``The Accused'' and Melanie Griffith as a businesswoman in ``Working Girl,'' but I'll go for Meryl Streep as an Australian woman accused of murder in ``A Cry in the Dark.''

Since the haunting ``Thin Blue Line'' wasn't nominated, my ``best documentary'' choice is ``Hotel Terminus: The Life and Times of Klaus Barbie,'' the overwhelming Marcel Ophuls documentary about a Nazi war criminal.

In the race for ``best foreign-language film,'' meanwhile, I vote for Pedro Almod'ovar's wacky Spanish comedy, ``Women on the Verge of a Nervous Breakdown.'' But the winner may turn out to be ``Salaam Bombay!,'' Mira Nair's drama about street children in India, or ``Pelle the Conqueror,'' the overrated Danish epic with Swedish actor Max von Sydow as a poor father raising his son in a strange land.

In the remaining categories, I'll let Oscar decide - and hope that next year the Academy takes more care to consider the whole 12 months it's supposed to consider.