Digital cinematography is the process of capturing motion pictures as digital images, rather than on film. Digital capture may occur on tape, hard disks, flash memory, or other media which can record digital data. As digital technology has improved, this practice has become increasingly common. Many mainstream Hollywood movies now are shot partly or fully digitally. Many vendors have brought products to market, including traditional film camera vendors like Arri and Panavision, new vendors like RED and Silicon Imaging, and companies which have traditionally focused on consumer and broadcast video equipment, like Sony and Panasonic. The benefits and drawbacks of digital vs. film acquisition are still debated, but digital cinematography cameras sales have surpassed mechanical cameras in the classic 35 mm format,[citation needed] and the Academy Award for Best Cinematography was awarded to a movie shot mainly digital in 2009.[1]
History
Beginning in the late 1980s, Sony began marketing the concept of "electronic cinematography", utilizing its analog HDTV cameras. The effort was met with very little success. In 1998, with the introduction of HDCAM recorders and 1920 × 1080 pixel digital video cameras based on CCD technology, the idea, now re-branded as "digital cinematography", finally began to gain traction in the market.
In May 2002 Star Wars Episode II: Attack of the Clones became the first high-profile, high-budget movie released that was shot on 24 frame-per-second high-definition digital video, using a Sony HDW-F900 camera. The lesser-known 2001 movie Vidocq was shot with the same camera.
In parallel with these developments in the world of traditional high-budget cinematography, a digital cinema revolution was occurring from the bottom up, among low budget filmmakers outside of the Hollywood system. Beginning in the mid-1990s, with the introduction of Sony's DCR-VX1000, the digital MiniDV format began to emerge. MiniDV offered much greater quality than the analog formats that preceded it, at the same price point. While its quality was not considered as good as film, these MiniDV camcorders, in conjunction with non-linear editing software that could run on personal computers, allowed a large number of people to begin making movies who were previously prevented from doing so by the high costs involved with shooting on film.
Today, cameras from companies like Sony, Panasonic, JVC and Canon offer a variety of choices for shooting high-definition video with less than $10,000 worth of camera equipment. At the high-end of the market, there has been an emergence of cameras aimed specifically at the digital cinema market. These cameras from Arri, Panavision, Grass Valley and Red offer resolution and dynamic range that exceeds that of traditional video cameras, which are designed for the limited resolution and dynamic range of broadcast television.
Technology
Digital cinematography captures motion pictures digitally, in a process analogous to digital photography. While there is no clear technical distinction that separates the images captured in digital cinematography from video, the term "digital cinematography" is usually applied only in cases where digital acquisition is substituted for film acquisition, such as when shooting a feature film. The term is not generally applied when digital acquisition is substituted for analog video acquisition, as with live broadcast television programs.
[edit] Sensors
Digital cinematography cameras capture images using CMOS or CCD sensors, usually in one of two arrangements.
High-end cameras designed specifically for the digital cinematography market often use a single sensor (much like digital photo cameras), with dimensions similar in size to a 35 mm film frame or even (as with the Vision 65) a 65 mm film frame. An image can be projected onto a single large sensor exactly the same way it can be projected onto a film frame, so cameras with this design can be made with PL, PV and similar mounts, in order to use the wide range of existing high-end cinematography lenses available. Their large sensors also let these cameras achieve the same shallow depth of field as 35 or 65 mm motion picture film cameras, which is important because many cinematographers consider selective focus an essential visual tool.
Television cameras typically use three 1/3" or 2/3" sensors in conjunction with a prism, with each sensor capturing a different color. Camera vendors like Sony and Panasonic, which have their roots in the broadcast and consumer camera markets, have leveraged their experience with these designs into three-chip products targeted specifically at the digital cinematography market. The Thomson Viper also uses a three-chip design. These designs offer benefits in terms of color reproduction, but are incompatible with traditional cinematography lenses (though new lines of high-end lenses have been developed with these cameras in mind), and incapable of achieving 35 mm depth of field unless used with depth-of-field adaptors, which can lower image sharpness and result in a loss of light.
[edit] Acquisition Formats
As far as digital cinematography is concerned, video resolution standards depend first on the frames' aspect ratio in the film stock (which is usually scanned for digital intermediate post-production) and then on the actual points' count. Although there is not a unique set of standardized sizes, it is common place within motion picture industry to refer to "nK" image "quality", where n is a (small, usually even) integer number which translates into a set of actual resolutions, depending on the film format. As a reference consider that, for a 4:3 (around 1.33) aspect ratio which a film frame (no matter what is its format) is expected to horizontally fit in, n is the multiplier of 1024 such that the horizontal resolution is exactly 1024n points. For example, 2K reference resolution is 2048×1536 pixels, whereas 4K reference resolution is 4096×3072 pixels. Nevertheless, 2K may also refer to resolutions like 2048×1556, 2048×1080 or 2048×858 pixels, whereas 4K may also refer to 4096×3112, 3996×2160 or 4096×2048 pixels.
The DCI standard for cinema defines 4K with 4096*2048 and 2K with 2048*1024.
Commercial cameras marketed as digital cinematography cameras typically shoot in progressive HDTV formats such as 1080p, 2K and 4K.
