Digital Projection

Biggar Little Cinema and Digital Projection

Our films are shown in high-resolution digital quality, and projected using the latest digital equipment on to a full-size cinema screen. To match the exceptional quality of our picture, our sound is Dolby stereo using high definition loudspeakers.

In recent years, high quality commercial cinemas have been changing over from traditional 35mm film to digital projection. Using this technology, the film is replaced by an electronic copy contained on a storage device, such as a high-capacity hard drive or dedicated DVD. Instead of projecting light through film, digital cinema utilises high quality digital equipment and projection to give a far superior picture on the screen.

To the audience, the most important aspect of cinema is the projection system. This is the final piece of technology controlling how the movie actually looks at the end of the line.

Digital cinema presentations provide a picture which is visually superior to film and with a more stable image. There are no ‘artifacts’ in the picture, such as scratches or spots. Digital presentations do not fade or suffer the other problems that film experiences, especially after being played for an extended time. In addition, there are no sound dropouts or jump or weave.

Our equipment comprises:

History of Digital Projection

In June 1999, digital projector technology was publicly demonstrated for the first time on two screens in Los Angeles and New York for the release of Lucasfilm's Star Wars: Episode I: The Phantom Menace. This movie had been shot on traditional film, and subsequently digitised in post-production. The first all-digital live action feature was Star Wars Episode II: Attack of the Clones. No film was used in the creation of the movie until film copies had to be made for theatres without Digital Cinema projectors.

Many filmmakers are using digital technologies to create their movies. George Lucas, who directed the Star Wars series among many others, has stated that all his future films will be shot digitally, and Robert Rodriguez, who directed Spy Kids, used digital cinema cameras to create 'Once Upon a Time in Mexico'.

Types of Digital Projection System

The first Digital Cinema installations used limited 1280×1024 resolution 1.3K systems, but those are no longer approved for use. Most Digital Cinema installations are 2K installations, with a resolution of 2048 x 1080 pixels.

Sony Electronics was the first to introduce 4K systems, which display images that are 4096 x 2160 pixels. Texas Instruments is also making 4K equipment for movie theatres.

The Digital Cinema Initiatives (DCI) specification for digital projectors calls for two levels of playback to be supported: 2K (2048×1080) or 2.2 megapixels at 24 or 48 frames per second, and 4K (4096×2160) or 8.85 megapixels at 24 frames per second.

Although there are four times as many pixels present in a 4K image than a 2K image, many movies are digitised at the 2K resolution and their special effects are also rendered at that resolution. It is very difficult to ascertain which movies might be produced using 4K resolutions, and there probably would be little to no benefit to viewing a 2K movie on a 4K system over a 2K system.

Studios will most certainly invest in higher resolution equipment in the future, and especially if 4K-capable projection systems become popular. Some movies have been restored using 6K scanners, so the technology is certainly present to capture very high resolution images from film, and rarely is more resolution a bad thing when it comes to image quality.

In 2010, the total number of digital screens worldwide was over 36,000, up from 16,300 at the end of 2009 or a growth rate of 121.8%. There were just over 10,000 digital screens in Europe as a whole (28.2% of the global figure), 16,500 in North America (46.2% of the global figure) and 7,700 in Asia (21.6% of the global figure). By the end of 2011, 72% of UK cinema screens had been converted to digital projection.

It has been estimated that, by the end of 2012, 80% of worldwide cinema screens would be converted to digital, and almost all of the rest would be converted by the end of 2015.

Projection Technology

Today, there are two major digital cinema projector technologies: Micromirror projectors and LCD projectors.

Micromirror projectors, like Texas Instruments' Digital Light Processing (DLP) equipment, form images with an array of microscopic mirrors. In this system, a high-power lamp shines light through a prism. The prism splits the light into the component colours red, green and blue. Each colour beam hits a different Digital Micromirror Device (DMD), a semiconductor chip that is covered in more than a million hinged mirrors. Based on the information encoded in the video signal, the DMD turns over the tiny mirrors to reflect the coloured light. Collectively, the tiny dots of reflected light form a monochromatic image.

To visualise how this works, imagine a crowd of people on the ground at night, each holding a square-foot mirror. A helicopter flies overhead and shines a light down on the crowd. Depending on which people held their mirrors up, a different reflected image would be seen. If everybody worked together, they could spell out words or form images. If there were more than a million people, pressed shoulder to shoulder, the most highly detailed pictures could be created.

In actuality, most of the individual mirrors are flipped from "on" (reflecting light) to "off" (not reflecting light) and back again thousands of times per second. A mirror that is flipped on a greater proportion of the time will reflect more light and so will form a brighter pixel than a mirror that is not flipped on for as long. In this way, the DMD creates a gradation between light and dark. The mirrors that are flipping rapidly from on to off create varying shades of grey (or varying shades of red, green and blue, in this case). Each micromirror chip reflects the monochromatic image back to the prism, which recombines the colours. The red, green and blue rejoin to form a full colour image, which is projected on the screen.

LCD projectors, such as JVC's Digital Image Light Amplifier (D-ILA) equipment, work on a slightly different system. These projectors reflect high-intensity light off of a stationary mirror covered with a liquid crystal display (LCD). To display images, LCD projectors typically send light from a metal-halide lamp through a prism or series of dichroic filters that separates light to three polysilicon panels – one each for the red, green and blue components of the video signal. As polarised light passes through the panels (combination of polariser, LCD panel and analyser), individual pixels can be opened to allow light to pass or closed to block the light. The combination of open and closed pixels can produce a wide range of colours and shades in the projected image.

VP-700 Metal-halide lamps are used because they output an ideal colour temperature and a broad spectrum of colour. These lamps also have the ability to produce an extremely large amount of light within a small area: current projectors average about 2,000 to 15,000 American National Standards Institute (ANSI) lumens.