A beginner’s guide to DVD, part 3
Brian Doxtader | Tuesday, January 18, 2005
Editor’s Note: This is the third in a three-part series on the basics of Digital Video Discs.
What is a DVD transfer?A transfer is the compression of film into digital information that is placed onto the DVD.What problems hurt transfers?A transfer is essentially the movement from one exhibition medium to another; a DVD will rarely look as good as film stock when projected. Accordingly, there can be various picture quality problems with DVD transfers.What is edge enhancement?Edge enhancement is the artificial sharpening of an image to compensate for the transfer to a digital medium. While this is generally not noticeable on a smaller television, edge enhancement on a larger display will cause haloing. Haloing is a picture imperfection caused by differences in light and/or color. It is comparable to the extraneous light caused by a streetlamp. Generally, it is better if a film is transferred without digital enhancement, but this can cause picture softness.Another potential problem is compression artifacting or digital artifacting. Artifacts are imperfections in the picture caused by poor compression of the digital information when placed on the disc. They appear as pixilation in otherwise clear prints and are usually noticeable and distracting.What is picture softness?Picture softness is the opposite extreme of edge enhancement. In this, the DVD is actually less detailed than the original film print. This is another result of switching between two different mediums. The effect of picture softness is an image that looks slightly out of focus. Again, this is more noticeable on larger displays than on smaller televisions.Original and remixed SoundSoundtracks should be clear and free of hiss, pops or crackles. Most studios are able to create clear sound-mixes, although many do not take advantage of surrounds and have most of the soundtrack mixed to the center speaker.When possible, a studio should maintain the original sound mix as intended by filmmakers. Often, however, they will remix the sound in a different format. Remixed soundtracks almost never sound the same as the original. For instance, James Cameron’s “The Terminator” has an optional 5.1 track in addition to the original mono; the differences in these tracks are immediately noticeable. Most frustrating is when studios place only remixed tracks onto DVD’s. Steven Spielberg’s “Jaws” is available in two separate editions: DTS and Dolby 5.1. Unfortunately, neither version contains the original mono soundtrack.RestorationMany older films undergo digital restoration before DVD presentation. Some companies such as Lowry Digital (“Indiana Jones,” “Star Wars,” “Citizen Kane”) and Criterion have become renowned for their restoration efforts.Restoration is a complicated and often difficult matter. Unlike straight transfers, the original negatives are usually in unpreserved shape, and, in the worst case scenarios, are completely destroyed altogether. Prints can have scratches, dirt, or tears that degrade the quality of the film, and thus, the DVD. This leads to all kinds of problems: un-restored transfers can range from “good” to “unwatchable”, depending on the source materials.Bringing old films back to life usually consists of (and requires) computerized digital cleaning of the print.Color prints are often even more difficult since older films used Technicolor’s three-dye process. This process created prints that faded over time, so older negatives of such films are colored incorrectly. Restorers thus have to use computers to re-color these films as accurately as possible. This often leads to problems akin to remixed audio: in many cases, the colors won’t be exactly the same as originally filmed. The original transfer of David Lean’s “Lawrence of Arabia” was color-timed incorrectly, but the newly restored Superbit re-issue has since corrected this issue. Additionally, bad compression or transfers can affect color levels, especially in black tones, which can look either splotchy or faded.In some cases, serendipity leads to excellent re-issues of older films. For instance, Carl Theodor Dreyer’s “The Passion of Joan of Arc” was thought to be lost forever to fire. However, a nearly-complete print in good condition was discovered in a mental institute in the mid-1980s. A complete restoration followed. Similarly, Criterion had prepared a transfer of Jean Renoir’s “The Rules of the Game” when new and better source materials surfaced; the company re-restored the film from this new material. Yet there are still problems with finding good source material. While Kino’s edition of Fritz Lang’s “Metropolis” is the best and most complete edition available, it is widely known that there are still considerable amounts of footage missing, probably gone forever.What’s Next?The final word comes in the form of a warning of sorts. The next wave of technology will soon be upon us, and a format war may be brewing, similar to the war between VHS and Beta. Sony (which recently acquired MGM’s catalog) is backing its own blue-laser technology, Blu-Ray, while Warner, Universal, New Line, and Paramount are all backing HD-DVD. While both technologies have their benefits and drawbacks, only time will tell which will emerge as the superior format. In the meantime, DVD is the best commercially available technology and has revolutionized the home theater market for the better.