The advantages & disadvantages of digital projectors

Film exhibition technology has matured and evolved since Edison Laboratories invented the technology a century ago. The basic concepts are still similar. In the early 2000s, the movie industry began switching from celluloid-based projection to digital projection. Digital projection has advantages and disadvantages.

Author Lev Manovich defines digital cinema as "live action material + painting + image processing + compositing + 2-D computer animation + 3-D computer animation." Live action material is filmed digitally, and then downloaded to a computer where image processing, compositing and editing are completed with digital sound created in a separate file or CD. The movie is then ready for distribution and projected onto the screen using a digital projector.

Analogue films need to be "made up" by connecting the reels that come in film canisters from the movie studio. A skilled projectionist takes about an hour to assemble one film, whereas digital films need only the click of a button or two to accomplish the same task. Fewer projectionists are needed to run the same number of screens in a multiplex. Studios ship analogue films in canisters to theatres, incurring large shipping costs. Digital projectors circumvent that because the file is downloaded the night before it is scheduled to play for next to no cost.

With a digital film, the 1,000th showing is as good as the first showing. This isn't always the case with analogue films, which can have scratches, breaks or other flaws. Files can become corrupted and computers can malfunction, but the quality is always exactly the same with digital.

Digital projectors also allow the exhibitor to show alternative content to films -- events such as concerts, sporting events or even opera. Digital projectors also offer anti-piracy protection. Digital cinema offers the ability to show 3-D movies. Analogue films have been made in 3-D, but they do not match the sophistication of 3-D technology.

The biggest stumbling block of digital projectors is cost. In early 2011, installation of digital projectors cost between £32,500 to £97,500 per auditorium. Retrofitting a multiplex with 12 screens could cost anywhere from half a million to £1.3 million. Digital is more expensive to operate on a daily basis because digital projectors use twice as much energy to operate and require larger lamps for projection that burn out quicker. Each digital projector also needs its own dedicated phone line, so that it can update content, encryption and other information on a regular basis.

For theatres in smaller cities and towns, maintenance and repair can be a major issue. In most theatres, staff is usually skilled enough to effect repairs if a projector malfunctions. However, digital projectors can only be repaired and maintained by studio-certified companies. This increases costs and may even lead to dark screens if a repairman cannot get to the theatre quickly enough, a potential issue in rural areas.