GLOSSARY OF TELECINE TERMS - Very Handy one.

GLOSSARY OF TELECINE TERMS


3/2 PULLDOWN - Since film is usually shot at 24 frames per second and video has 30 frames per second, we need to make up 6 frames per second when transferring film to video. This is done by adding an extra field to every other film frame, (there are 2 fields per video frame), resulting in a field sequence of AA, BBB, CC, DDD etc. This process is called 3/2 pulldown. There is no 3/2 pulldown when the film was shot at 30fps in NTSC, or 25fps in PAL because in these cases the film and video are running at the same rate, (1 film frame per 1 video frame).

AATONCODE - (similar in concept to Arri FIS). A code exposed along the edge of the film at the same time the image is exposed. AatonCode contains time code, shoot date and camera I.D. information. Only certain cameras can expose this code. AatonCode contains the same time code as that being recorded simultaneously on the audio deck. During film transfer, AatonCode is decoded by a reader attached to the telecine, (Keylinker). The audio locks to the matching AatonCode and automatically syncs with the picture. This eliminates the need for a slate during shooting since sync can be determined at all times via the AatonCode. (A visual/audio slate such as a clap-board or smart-slate can be used as a back-up.)

ANALOG / DIGITAL - An example of analog: a plucked guitar string vibrates the air around it. These air waves in turn vibrate a small membrane in a microphone. This membrane translates those vibrations into fluctuating electronic voltages. During recording to tape, these voltages charge magnetic particles on the tape, which when played back will duplicate the original voltages, and hence the original sound. Recording pictures works similarly, except that instead of air vibrating a membrane, fluctuating light strikes an electronic receptor that changes those fluctuations into voltages. Analog describes real world sound and images that have been translated into continually changing electronic voltages. In the digital world, the same varying voltages are sampled or measured at a specific rate, (e.g. 48,000 times a second or "48K". Because of sampling, a digital signal is segmented into steps that define the overall quality of the signal. A signal sampled at 48K is better than one sampled at 44.1K. These samples are represented by bits, (0s and 1s) which can be processed and recorded. The more bits a sample has the better the picture or sound quality, (e.g. 10 bit is better than 8 bit). A good digital signal will have a high number of samples, (sampling rate) and a high number of bits, (quantizing). Digital processing clears the way for multiple, perfect copies or "clones", because it is the bits that are copied instead of the analog voltages.

ASPECT RATIO - Refers to the ratio of width to height of an image. Standard television aspect ratio is currently four units wide by three units high, or 4:3. Super 16mm aspect ratio is 15:9, or said another way, 1.66 units wide for every 1 unit high, otherwise listed as 1.66:1 (read 1.66 to 1), or simply ìone-six-sixî. High definition television (HDTV) is slightly wider at 16:9 or 1.77 units for every 1 unit high ("one-seven-seven"). Even wider still are theatrical projections with common aspect ratios of 1.85 and 2.35. An entire wide screen image displayed on a regular television will have a black band at the top and bottom. This is called letterbox.

CENTER TRACK TIME CODE - A time code signal recorded along the center of a 1/4" audio tape. This signal is used as a locating tool when syncing audio to film. It is also used to make sure the tape plays back at the exact speed it was recorded in the field, (this is called resolving). Often, time code is striped onto tapes that have Neopilot before a film transfer session begins.

COLOR CORRECTION - This term might be better thought of as "color enhancement" or "color manipulation". Why do film and video images need color correction?

A) Film has a much wider contrast and color range than video. Color correction allows the colorist to adjust these characteristics to meet the producers needs.
B) Shooting situations are not always ideal and are often spread out over time. Color correction provides a controlled environment to match scenes from differing conditions.
C) Sometimes a special effect is needed where unusual colors or textures are desired.

The following are terms used to describe the level of color correction used for a color correction session:

Scene-by-Scene - The highest level of color correction. The colorist uses any available technique and makes as many color corrections as necessary to create the best possible image from a film or tape source. In addition, the colorist matches each scene to the rest of the project to achieve an overall look consistent with the desires of the producer. The resulting transfer will be suitable for any end use.

Best Light - The middle level of color correction. Each scene is color corrected but not matched to any other scene. The colorist will stop as often as necessary to adjust for scene or lighting changes. The resulting transfer will be suitable for stock libraries, editing, (especially when the edit source image quality must be appealing), and final scene-by-scene tape-to-tape color correction. (Only used during film-to-tape-transfer.)

COLOR TEMPERATURE - A measurement of the color tint of a white light source. This is expressed in degrees Kelvin (K). The bluer or "cooler" the light the higher the number, the redder or "warmer" the light the lower the number. A normal light bulb is around 3200K, normal daylight is around 6000K. Television monitors are on the cool side with a U.S. standard set at 6500K.

COMPOSITE PRINT - A film print with a sound track printed on the film. This can be a magnetic sound track, but most often is an optical track.

DAILIES - Originally this term referred to the "rushes" or "daily" workprint created overnight for a feature film director/crew to view in the morning, so they could see if they got their desired scenes before striking the sets. In the video world "dailies" came to mean a quick transfer of original negative so that a spot could be viewed and edited on a 3/4" system etc. before returning to a telecine suite for the real transfer session. Currently dailies also encompass transfer of original documentary negative to video for off-line editing purposes. Later this footage might return to telecine for a tape-to-tape color correction session. The overall similarity of these scenarios is that the dailies are not the final color correction for the footage, but rather a way to be able to view and edit the material before bringing a cut-down version back to telecine for more critically matched corrections.

EDGE NUMBERS / KEY NUMBERS - These numbers are printed by the manufacturer at 1 foot intervals, (35mm) and 1/2 foot intervals, (16mm), on the edge of raw film stock . They act not only as a footage counter and location marker on the stock, but also contain film type and manufacturing batch codes. Edge numbers / key numbers on a workprint copy are used to locate scenes from the original negative. See also Keykode, a bar-coded format of key numbers.

FLEX FILE - A computer generated file that keeps track of 3 different codes and other information at any given point. Most importantly, this file establishes the relationship of video time code to film Keykode, but can also include audio time code, (or AatonCode). Flex files are used in off-line systems, or by a film lab to trace a video EDL back to original camera negative (via Keykode), so that the film can be cut into a finished print. In addition, select reels for a final film-to-tape color correction can also be made. Flex files also have the ability to log slate information such as "scene", "take", "camera roll", or "audio roll", at each camera stop. Most often only the "headpunch" of each camera roll is logged to establish the video time code to Keykode relationship for each roll. (If AatonCode is on the film, all camera stops can be logged automatically).

KEYKODE - Eastman Kodak encodes edge numbers into a bar code format called Keykode. These bar codes are printed by the manufacturer at 1/2 foot intervals on the edge of 16mm negative, and 1 foot intervals on 35mm, along with edge numbers or ìkey numbersî that are readable by eye. Keykode allows machines to electronically read key numbers as the film passes through a reader attached to the Rank. Keykode / key numbers act as a sort of time code for film, providing location information as well as film stock type and batch codes.

LATENT EDGE NUMBERS - Edge numbers that have printed through from one film stock to another, e.g. from negative to a workprint copy.

MAG FOLLOWER - The machine that plays mag track audio. This machine interlocks with the telecine for sync audio, and can handle 35mm 3 & 4 track formats as well as 16mm 1 & 2 track formats.

MAG TRACK - Audio track recorded on 35mm or 16mm oxide coated stock. Mag stock has the same dimensions and sprocket holes as film stock. This format is not used for original field recordings, but rather as a secondary or mix use. For those using flatbed editing systems, original field audio is dubbed to mag stock, then the workprint (picture), and mag audio are edited in unison. 35mm mag offers 3 or 4 track formats, while 16mm offers 1 or 2 tracks.

MAG STRIPE - Refers to a thin strip of magnetic oxide on the edge of picture film, that contains a single audio track. A small audio head attached to the telecine reads the audio during the transfer.

MATCHBACK - The process of cutting camera original film using a video EDL. Currently, more editors are choosing to work on a non-linear video off-line system like the ìAvidî instead of a flatbed editing system like the "Steenbeck". This means all film and audio must be transferred to a video format for input into the off-line system. After the off-line editing is complete, a producer may wish to return to the camera original film to either assemble a print for projection, or to assemble reels of selected takes for a scene-by-scene color correction, (before the final on-line). To accomplish this match back to the negative, a Flex File is generated during the initial transfer, to mark video time code and film Keykode relationships at the beginning of each camera roll.. This provides a list so that a video EDL can be translated into a Keykode EDL which the negative conformers use to cut the film.

NAGRA - A 1/4" audio machine made by "Nagra-Kudelski" of Switzerland. Those who record 1/4" audio in the field use Nagras almost exclusively. The pilot system allows for the playback of audio at the precise speed it was recorded on location. Studio Nagras can handle both neopilot (more common), and F.M. pilot, as well as center-track time code at all standard speeds, (15ips, 7.5ips, 3.75ips). They are stereo, (two track) decks that can be synced with the telecine, VTR's, or used as a source deck in an edit suite.

NOISE REDUCER / ENHANCER - The magic box in telecine that reduces electronic "noise" and film grain, while simultaneously enhancing or sharpening the picture. Both attributes can be dialed in to varying degrees. The telecine signal always passes through this box, with "normal" settings for noise reduction and enhancement in place.

OPTICAL TRACK - An audio track in the form of a stripe down the side of a film print. A light source on the projector or telecine shines through this stripe. Because of changes in the pattern of the optical track, the light is modulated as it strikes an electronic receptor, which translates the information into an audio signal. A film print with an optical track is also referred to as a composite print, or called a print SOF which stands for "sound on film". Most release prints have optical sound tracks, e.g. movies at theaters.

PILOT - A signal recorded by Nagras on 1/4" tape to ensure that audio will play back later at precisely the same speed it was recorded in the field. When a playback Nagra locks onto this signal, the pilot is being resolved, or played back at the proper speed so that the sound will stay in sync with the picture. There are two types of pilot in use. The more common version is neopilot which is used on mono audio recordings only. F.M. pilot is used with 2-track or stereo recordings. To be able to sync audio in telecine, time code is needed on the tapes instead of pilot. Neopilot tapes are striped with center track time code, whereas F.M. pilot tapes need to be dubbed to another audio tape because of technical reasons. All striping and dubbing should happen before the transfer session.

SLATES - A visual marker used during filming to provide production and scene information. Also a visual and audible marker for syncing picture and audio later in post production. There are several different methods of slating: A smart slate provides a readable time code display on a clapper board. This time code is the same that is being recorded simultaneously on the audio tape. By stopping on any frame and reading the displayed time code, one can find that exact point on the audio tape, then lock the audio to the film for sync sound. A bloop slate is basically a box with a light bulb or a 2 digit number display. When a button is pressed the light(s) illuminate and a tone is recorded onto the audio tape. By lining up the light with the sound beep, sync is achieved. Clap sticks are the most traditional, with the clap of the wood as the sync reference. Of these methods, smart slates are the fastest and most accurate. Head slates, those that appear at the beginning of a sound take, are far preferred over tail slates in which the marker is provided at the end of the take, (usually with the slate upside down to denote a tail mark).

SYNC TAKES - Segments of film with simultaneously recorded audio that are marked with a slate so that they can be easily synced or "locked" together in post production.

TELECINE - The machine used to transfer film to videotape. The telecine acts as an electronic film projector, shining light through the film, then turning it into an electronic signal. After color correction, the signal is formed into a video picture that can be recorded onto a videotape.

TIME CODE - An electronic code recorded on audio and videotape that acts as a location marker or time reference for the recorded material. Professional video systems rely on time code for cueing and editing. A video EDL consists mainly of time code ìinsî and ìoutsî to direct an editor to the beginning or end of scenes.

TLC - Time Logic Controller, the editing system for telecine. This machine controls the telecine and up to four VTR's simultaneously with field-accurate editing and full 3/2 pulldown management.

ULTRASONIC FILM CLEANER - A device that runs film through a heated bath of fluid which is vibrated at ultrasonic frequencies. Jets of fluid and swirling buffers add to the cleaning power. Finally, the film is run through a heated air dry system before winding onto a take-up reel.

USER BITS - A section of the time code signal that provides 8 digits which can be programmed by the user for organizational purposes, (e.g. show codes or tape reel numbers). User bits are limited to the numbers 0-9 and letters A-F, and usually remain static, (as opposed to running like time of day).

VARI-SPEED - Refers to film or tape running at any non-standard speed.

WETGATE - A device that allows film to be projected through a chamber of liquid in order to produce a scratch and dirt free transfer or print. A scratch or mark in the film is visible because light refracts on the edges of the scratch itself. As light passes through the image using the Wetgate system, fluid fills the scratch and stops the refraction so that the imperfection is invisible, (some scratches on the emulsion side may not be removed). A Wetgate is a good problem solver, but has a few disadvantages. Because the film passes through a fluid, and needs to dry before winding on a take up reel, high speed winding is not feasible. Also, the fluid used in these gates is an ozone depleter, and very expensive since its production has been restricted by the government. See also Digital Wetgate.

WILD SOUND - Sound that isn't meant to sync with picture, e.g. room tone, birds chirping, flags waving in the wind etc. This sound is used as background or as ambience. Wild sound might also include voice-over audio that was recorded without picture, e.g. off camera interviews or spot disclaimers.

X-Y-ZOOM - A feature of the telecine that allows the image to be moved left or right (X), up and down (Y), or in and out (Zoom). Although the picture can be degraded if zoomed in too far, it is better for an image to be re-framed in telecine rather than with a DVE in edit.