Page 5: Technical Information

Bleach Bypass  -  Digital Intermediate  -  Steadicam


From First Cameraman to Director of Photography  -  The documentary 'The Cinematographer'  -  What Is a Director of Photography? [by Gregg Toland & Charles G. Clarke]


Film vs. Digital Video  -  D-Cinema


Oliver Stapleton: So You Wanna Work in Movies?


What It Took to Create 'Collateral'


Bleach Bypass  -  Digital Intermediate  -  Steadicam


A History of Aerial Cinematography


Wizards of Visual Effects: The Golden Age

>  A color processing technique in which the bleaching stage is omitted or reduced, which results in silver grains remaining in the emulsion. Such images have, therefore, both the color layers and a black and white image superimposed upon each other.
Bleach Bypass is commonly used in cinematography, as it results in a desaturated effect in images and can be used to extend the dynamic range of the emulsion somewhat. It can be done to positive prints or, less commonly in motion picture work, the negative.

>  A film laboratory technique where, by skipping the bleach stage in the color processing sequence, silver is retained in the image along with the color dyes. The result is effectively a black and white image superimposed on a color image. Bleach Bypass images have increased contrast, reduced saturation, often giving a pastel effect.

>  Eastman Kodak: The terms 'skip bleach', 'bleach bypass', 'ENR', etc, refer to a number of related proprietary processing techniques currently being offered by some motion picture laboratories as a means of increasing contrast, darkening shadows and reducing the color saturation of images. Since these techniques represent departures from normal recommended practices, Eastman Kodak Company has been asked to comment on their use by laboratories.
Whereas skip-bleach techniques may sometimes give desirable results from a creative perspective, Eastman Kodak Company cannot guarantee product performance nor assume any responsibility or liability for its products when they are processed under non-standard conditions.

Background Information

A number of related processing techniques currently experiencing some popularity in the motion picture industry are called 'skip-bleach', 'bleach bypass', 'ENR', etc. These techniques are employed in certain film productions to create special looks or moods. They are accomplished by a variety of techniques, which allow some or all of the image silver, which is normally removed by bleaching and fixing, to be retained in the film along with the image dyes. The retained silver increases the contrast of the image and decreases the color saturation by adding gray or black to the dye images. Skip-bleach techniques can be applied to the processing of the camera original negative, the intermediate positive, duplicate negative or final print, or any combination of these stages.
Different results are achieved according to which step the skip-bleach technique is applied. When applied to an original negative, the effect seen on a print made from the negative results in lighter and possibly blown-out highlights, higher contrast and perhaps higher graininess. When applied to the print, the effects are mainly seen in the shadows, which will be darker, richer, with higher contrast, less detail [possibly blocked-in] and with desaturated, muted colors. These effects can be very scene-dependent.
There is a common belief that if a skip-bleach technique is used with camera original film and is later determined to be unsatisfactory, the film can simply be reprocessed normally to restore its integrity. Reprocessing of camera original film places it at risk because of extra handling and should be done only as a last resort. In addition, if any allowances were made for skip-bleach in the exposure of the film, such as underexposure or the use of flat lighting to compensate for the increased density and contrast caused by the retained silver, then reprocessing to remove the retained silver will produce a thin, underexposed 'flat' negative with smoky shadows and possibly higher grain. [From the Eastman Kodak website.]



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>  In the international movie industry, 'digital intermediate' has grown into a buzzword for a wide range of technical processes associated with bringing a movie into the theatre. 'Digital intermediate' encompasses the full range of technical processes in which a moving image from a digital source, direct or scanned from film, is manipulated, matched with the proper sound in digital format, and prepared for viewing.
Viewing may be:
- By feeding a data-source into a projector as used in a digital cinema;
- In a regular cinema after image and sound have been rerecorded onto 35mm film;
- From DVD or tape after image and sound have been converted to a video signal.

>  A 'digital intermediate' is a process by which sections of, or the entirety of a motion picture is digitized through the use of a 35mm film scanner, into digital image files, manipulated in some manner, typically with color grading and digital special effects, and displayed or projected, either in a digital form, also known as digital cinema [D-Cinema], or recorded to film, using a laser film recorder, for traditional film projection.

Original Film Negative

Digital Intermediate Process

Film Scanner

Conforming Workstation

Film Recorder


Release Print

Optical Film Process

Cut Negative

Optical Grading and Timing



Release Print

'In the last year or two, the price of scanning film and recording it back to celluloid has come down so much that it is now economically feasible to bring an entire show into the digital domain, work with it there and record it out, ready for printing in the laboratory. The term 'digital intermediate' has come to be used for this process, and though it is still so new that in some cases it is being redefined with each show, the fundamental creative and technical advantages may soon make it a standard part of post-production for many features.

Creative Benefits

What does the 'digital intermediate' process offer? Most important, it provides unprecedented control over film color. Once your show is digitized, all the sophisticated color correction tools that are standard in video become available for film. Dark, medium and bright parts of an image can be timed separately, contrast can be adjusted, color can be changed gradually within a shot, 'power windows' can alter specified areas within the frame, and secondary color correction, where each color can be tweaked individually, is available. All of this happens in real-time, and with random access to the entire show.
This degree of control is available for entire features, allowing the creation of a look that would otherwise be impossible or require relatively unpredictable custom processing. One of the first films to use 'digital intermediate' for stylistic purposes was 'O Brother, Where Art Thou?' by the Coen brothers [ph: Roger Deakins].
Another major advantage 'digital intermediate' offers is that color correction is done only once, and the resulting file is then used to produce film and all video versions. Directors, cinematographers and editors can control and approve in one place the timing of all versions of their show and take care of other tasks, such as pan and scan and letterboxing, at the same time.
Not only can a show be color corrected in ways not previously possible, but the fact that the entire show will be manipulated digitally extends the creative palette and gives production the freedom to use more visual effects. As a result, it might allow some shows to shoot faster and, for better or worse, with less discipline. For example, a period piece could shoot with modern airplanes or TV aerials visible, knowing that they could easily be removed later. 'Digital intermediate' also provides an elegant way to combine footage shot in different formats, be it film or video.
The process isn't free - traditional lab work is still cheaper for film delivery alone, and it takes more time than traditional film timing. But 'digital intermediate' combines many processes and many budget items. The combined line items for film and video timing, titles and bread-and-butter opticals [fades and dissolves] can typically pay for a full digital finish. And prices will inevitably come down.

Scan Sizes

Scanning film takes time, and time is money. The result is that filmmakers and vendors must make choices about how much data is scanned from each frame. This number, the scan resolution, influences the economics of the entire process. Scans are measured in thousands of pixels of horizontal resolution. One 'K' means 1,024 pixels. A full-aperture '4K' scan has 4,096 pixels horizontally, and 3,112 pixels vertically. 4K is the current gold standard, and it's intended to faithfully record every single detail of the underlying film. 2K scans are less expensive and more common: 2,048 x 1,556 pixels to each frame. They yield files that are only a quarter the size of 4K scans: about 13 MB vs. 52 MB per frame.
How do these resolutions compare to film? Theoretically, based on the grain structure of the emulsion, film could be pegged as high as 6K. Practically, however, this is only true for first-generation camera original and only under ideal conditions. In practice, negative film is typically assumed to have a maximum resolution of about 4K. Release prints from an inter-negative, depending who you talk to, are said to have a resolution of well under 1,800 pixels across, and the projected image may actually be worse because lamps can be misaligned, and lenses can be dirty or out of focus.
What is the right scan size for 'digital intermediate'? Purists say that 4K is the only way to go. But many people say that 2K is more than good enough for theatrical distribution, since it offers as much or more resolution than the film prints we're seeing now.

Workflow Choices

The simplest 'digital intermediate' process entails scanning a cut negative. The resulting file can be color corrected, titles can be added, and some effects work can be done. This is the process that has been used most often so far. It's straightforward and relatively economical. But it's tantalizing to consider the possibility of scanning uncut negative. This would theoretically allow a show to be re-cut in the workstation, without the limits that negative splices now put on the release process - you'd build the show digitally and simply film it out. But the more you scan, the more money you spend and the more potential for confusion you introduce.
Once the show is scanned and visual effects are incorporated, color correction can be done with several systems. Digital timing offers capabilities that film professionals have only dreamed about in the past, allowing the look of a show to be refined in ways that were formerly impossible by any means. According to Bruce Everett, co-producer of HBO's miniseries 'Band of Brothers' [ph: Remi Adefarasin & Joel Ransom], the stylized colors of the show were created entirely in post. After desaturating, 'squashing' and tinting the image, secondary color correction was used to get skin tones, muzzle flashes, etc. back to a more natural look.
One critical issue for color correction is fidelity from the timing environment to the final film print. Monitoring can be done on specially calibrated high-definition video projectors or on CRTs. The goal is to pre-visualize the final film look as accurately as possible, and no system is perfect. It is this area of color fidelity that has seen some major hiccups in the past. Cinematographer Conrad W. Hall, who used the 'digital intermediate' process for 'Panic Room', says that the colors and brightness of the projected image changed during the six weeks that he spent in color correction. But he adds that this and other bugs will be worked out as more people use the process and the technology matures. In his view, the creative freedom afforded by 'digital intermediate' was more than worth the trouble and time involved.
Once a show is color-corrected, it must be recorded out to film. Outputs can be made to inter-positive, from which inter-negatives are made in a traditional lab process, or each printing negative can be output individually. That's more expensive, but it produces better quality - every print is generationally closer to the original negative.

The Future

In an environment where video acquisition is starting to make inroads in feature production, 'digital intermediate' offers a new lease on life for celluloid, giving filmmakers many of the creative tools that their TV counterparts have used for years. At the same time, the process takes us one step closer to a full digital workflow where all circled takes are scanned and a cut show is built entirely in the digital domain. Though we're not quite there yet, as prices come down, some type of 'digital intermediate' process may soon seem like a creative no-brainer for any show that will be released on film.' [From an article by Rainer Standke in the Editors Guild Magazine, May-June 2002.]

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Conceived and developed by Garrett Brown in 1973, the original concept was to find a way of capturing smooth hand-held action sequences while moving over uneven terrain, or though a crowd. Brown named his invention 'The Brown Stabilizer'. After completing the first working prototype, Brown shot a 10 minute demo reel of the revolutionary moves this new device could produce. The reel was seen by numerous directors, among others Stanley Kubrick and John Avildsen.

Stanley Kubrick & Garrett Brown

Operator George Richmond - "Goal!" [2005]

In 1974, Cinema Products Corporation [CPC] purchased Garrett Brown's invention and officially changed the name to Steadicam.
The original Steadicam made its debut in 'Bound for Glory' [d: Hal Ashby; ph: Haskell Wexler] in 1975 with Brown as the worlds first Steadicam operator. Soon after, Steadicam quickly revealed its enormous potential with the incredible action sequences captured in 'Marathon Man' [1975, John Schlesinger; ph: Conrad L. Hall; special ph: Garrett Brown], 'Rocky' [1976, John Avildsen; ph: James Crabe; spec camera efx: Garrett Brown] and 'The Shining' [1978, Stanley Kubrick; ph: John Alcott; co-Steadicam op: Garrett Brown].
In 1978 Garrett Brown and CPC received an 'Oscar' for technical achievement of the Steadicam.
Shortly thereafter, a range of other Steadicam Camera Stabilizing Systems followed, along with a new type of highly skilled and sought after professional, the Steadicam operator. This has now developed into a specialized association of operators, the Steadicam Operators Association, Inc. [SOA], which was formed by Garrett Brown and Nicola Pecorini in 1988 to connect skilled Steadicam Operators with motion picture directors and producers.
In 2000, The Tiffen Company purchased CPC. Since then, the Steadicam engineering and design staff at Tiffen, along with Garrett Brown and colleagues, has continued to develop new Steadicam systems.

Garrett Brown

A tripod or other mount normally supports a motion-picture camera. However, when supported by its operator alone, in what is described as 'hand-held' camera work, the projected image resulting normally shows the effects of even small body movements of the operator, even while he or she is standing still.
A Steadicam mounts the camera to the operator's body and provides him or her with a freedom of movement comparable to a hand-held camera. The Steadicam's armature absorbs the jerks, bumps, and other small movements of the operator, while smoothly following the broad movements needed to cover any given scene, such as moving over uneven terrain or through a crowd.
The Steadicam consists of a harness or supportive vest, worn by the operator, attached to an iso-elastic arm. This is in turn connected by a gimbal to the Steadicam armature [sled] which has the camera mounted at one end and a counterbalance weight at the other. The counterbalance usually includes the battery pack and a monitor. [The monitor substitutes for the camera's viewfinder, since the range of motion of the camera relative to the operator makes the camera's own viewfinder unusable.]
The combined weight of the counterbalance and camera means that the armature bears a relatively high inertial mass which will not be easily moved by small body movements from the operator. The freely pivoting armature - not the harness itself - accounts for most of the stabilisation of the photographed image.

Garrett Brown holds 50 patents worldwide for camera devices including the Steadicam JR for camcorders, the SkyCam, which flies on wires over sporting events, the MobyCam [1992], the underwater camera that chases the swimmers at the Olympics, the DiveCam [1996], the GoCam, the FlyCam and the SuperFlyCam, an ultra-light aerial film camera. And coming soon the MoleCam...





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