Entertainment

WATCH: ‘Titanic’ a must-sea in 3D

James Cameron’s spectacular new 3-D version of “Titanic’’ is everything I’d hoped for, and more. He judiciously — and sometimes with great subtlety — uses the technology to make a great film even greater.

From the already breathtaking sinking sequence to Kate Winslet’s brief nude scene, this redo breathes new life into the multiple-Oscar-winning picture.

Cameron, who has been vocally critical of the post-conversion of conventionally filmed movies to 3-D, has obviously taken great pains in using stereoscopic technology to enhance the experience of watching his swooningly romantic and dazzling Best Picture of 1997.

In fact, the 3-D in “Titanic’’ is more effective and immersive than for most films I’ve seen that were originally filmed in the process.

And though “Titanic’’ is a half-hour longer than Cameron’ s “Avatar’’ — which was shot in 3-D from the get-go and dethroned “Titanic’’ as the No. 1 grosser in 2009 after the latter spent 12 years at the top — I actually found it less of a strain on the eyes.

For starters, the 3-D makes the doomed ship, its decks and corridors look even longer and more vast — an amazing, wood-paneled stage on which to play out one of the most enormous tragedies of the 20th century.

The spectacular effects — mostly not digital — in the hour it takes for the ship to plunge into the ocean are more jaw-dropping in 3-D.

With added depth, the iceberg-stricken vessel rising vertically in the water, breaking in two and sliding under the waves is even more awe-inspiring than it was at first sight in late 1997, when “Titanic’’ began a still-record 15 weeks at the top of the US box office.

It helps that Cameron originally filmed “Titanic’’ in a relatively classic style, so there are few of those MTV-like quick cuts that can be so jarring in 3-D, which requires more time for your brain to process edits (so they don’t become a blur).

“Titanic’’ became a sensation not just because of its spectacle — of which there is plenty — but because of a timeless love story that rivals “Gone With the Wind,’’ and it’s here where Cameron deploys 3-D with a lighter touch to enhance the story.

This is apparent in the crucial scene in which Rose, Winslet’s teenage Philadelphia socialite, contemplates suicide by jumping off the ship’s stern to escape a stifling arranged marriage to the controlling millionaire Cal (Billy Zane).

She is rescued, of course, by DiCaprio’s penniless artist, Jack, in a sequence that is both more terrifying and intimately romantic with a third dimension added.

Winslet’s bravura, Oscar-nominated performance as the newly liberated Rose dominates even more fully in the 3-D version (which is otherwise identical to the original 195-minute theatrical cut).

That short nude scene — in which Jack sketches the voluptuous Rose wearing the Heart of the Ocean necklace — is now even more memorably eye-popping, as is their courtship dance and the discreetly filmed consummation of the class-defying relationship in Cal’s car, stowed below deck.

Later, Rose’s frantic attempts to rescue a trapped Jack from below the deck of the sinking ship are also enhanced. Viewers will notice how Cameron deploys 3-D to emphasize the ax that Rose uses on Jack’s handcuffs in a reciprocal act of liberation.

As the star-crossed couple struggles to stay alive in the icy North Atlantic after the ship goes down, there’s now an added dimension to their four-handkerchief parting. As there also is in the wonderfully symbolic gesture by the 101-year-old Rose (Gloria Stuart) that perfectly bookends the story.

This is a grand way to mark the centennial of the ocean liner’s famous sinking on April 15, as well as the film’s 15th anniversary and the 100th birthday of the film’s North American distributor, Paramount Pictures. (The film was co-financed by 20th Century Fox, which holds international rights.)

Even with some tin-ear dialogue — the 14 Oscar nominations (11 statuettes were awarded) notably did not include Cameron’s screenplay — “Titanic’’ is still one of my favorite movies of all time.

The addition of 3-D this good more than justifies another big-screen voyage — I’d even spring for the IMAX version, which was not available for advance screening.

Now I’d like to know: When do we finally get the 3-D revamp of “The Wizard of Oz’’ that Warner Bros. has been commissioning tests on for years? I can’t wait.

lou.lumenick@nypost.com