What's the point of seeing older films in a high-definition format such as Blu-ray?

Last week, I noted that the Criterion Collection planned to start releasing some of the vintage films in its catalog on Blu-ray, but I received unexpected reader feedback.

"So these will be high-def versions of the grainy originals? How does that work?" a reader named Chris asked on my blog.

I thought Chris was being sarcastic, but after another reader chided him, someone else thanked him for asking "a question that undoubtedly many nonfilm snobs were wondering as they read the article."

The issue is relevant now, because several older movies made from the 1960s to 1980s are coming out Tuesday on Blu-ray. They are a set of all of Clint Eastwood's "Dirty Harry" films (Warner, $130) and five World War II movies from Fox and MGM: "The Longest Day," "The Sand Pebbles," "Patton," "A Bridge Too Far" and "Battle of Britain" ($40 each).

The simple answer is that Blu-ray allows movies to be viewed essentially at film resolution. As good as standard DVDs look, they still aren't of the same image quality that you'd see of a properly projected film in a theater. Blu-ray offers comparable quality in image and sound.

For a more detailed answer, I called on film preservationist Robert Harris, who has restored classics such as "Lawrence of Arabia," "Vertigo" and "My Fair Lady."

His first reaction was to point readers to Warner's stunning presentations of "The Adventures of Robin Hood," "Casablanca" and "The Searchers" as evidence of how important high-def is to movies made as long as 70 years ago. (Only "The Searchers" is out on Blu-ray. The other two were released on the now-obsolete HD DVD format, but will be rereleased at some point on Blu-ray.)

"The most basic point is that there is no difference between a film made today or 70 years ago," Harris said. "They all have a certain grain structure, based upon the way that they were shot and the stock available at the time.

"Neither color nor the gray scale of black-and-white can be fully and properly represented in standard definition. Only in high-def or higher resolution is the accuracy of the color, densities, black levels and grain able to be reproduced."

He added: "Once the viewer gets used to watching material in Blu, it is very difficult to return to standard definition on anything larger than a 40-inch screen."

I can certainly vouch for that. I watch Blu-ray movies projected on an 8 1/2-foot screen. At that size, the difference between standard DVDs and high-def discs is substantial.

It's not just the latest big-budget blockbusters, either. "The Longest Day," a 1962 black-and-white movie about D-Day, looks pristine in its Blu-ray presentation. Harris hailed the image quality of "Battle of Britain" as being "sharp as a tack" and called the new disc of the 1969 film "a great Blu release on every technical level."

Harris added an important point: "Does the difference matter on a low-end 19-inch screen? Probably not. But especially with today's home-entertainment systems attempting to replicate the theatrical experience, standard definition is so far out of the loop that it hardly counts anyone."

Digital bits

Speaking of Blu-ray, former HD DVD backer Paramount Home Entertainment is catching up a bit with Tuesday's Blu-ray releases of its previously issued new movies "Cloverfield" and "There Will Be Blood."

Just a heads up that the complete "Get Smart" coming Tuesday is the short-lived 1990s revival of the comic spy series starring Don Adams (Sony, $20), not the 1960s original. The five-season run of the latter continues to be available only from Time Life (www.timelife.com) in a 25-disc set for $200. HBO is set to release DVDs of the original show in retail stores eventually, but no date has been announced.

Randy A. Salas • 612-673-4542