La registrazione su film di trasmissioni TVe la produzione di film col metodo televisivo

della TV, poteva anche, sotto determinati aspetti, convertirsi in un ottimo affare.

Ed ecco sotto questo profilo sorgere l'industria per la produzione dei film per TV.

La televisione è una insaziabile divoratrice di film : si è ormai visto che il film costituisce per la TV un'ancora di salvezza nel mare tempestoso dei programmi.

Sta perfino profilandosi la tendenza di filmare in precedenza i programmi televisivi per trasmet- terne poi la sola registrazione su film, con migliore risultato tecnico della stessa ripresa diretta.

La TV può quindi costituire per il cinema una nuova fonte di proficua attività produttiva.

Se a ciò si aggiunge la possibilità recentemente e brillantemente dimostrata di proiettare la TV su- gli schermi delle sale cinematografiche con pro- grammi specialmente allestiti per tale tipo di vi- sione, integrando il normale spettacolo cinemato-

grafico con la proiezione di riprese dirette di spet- tacolo di varietà, od attualità sportive o sociali, è facile giungere alla conclusione di una sempre mag- giore possibilità di intesa fra cinema e televisione.

Ed è su questa possibilità di « entente cordiale » che sarà imperniato in massima parte questo nostro Congresso.

Con questa anticipazione non esito ad esprimere la mia assoluta certezza sulla riuscita più completa del 3° Congresso di Tecnica Cinematografica « Ci- nema e Televisione » che inizia ora la sua breve in- tensa vita.

Ringrazio in modo particolare, anche a nome di tutti i congressisti, il Sindaco di Torino Avv. Pey- ron, che ha voluto offrire a nome della Sua cittadi- nanza questo simpatico e signorile ricevimento di apertura del Congresso.

Alessandro Banfi

nique pour son hospitalité si appréciée et la collaboration qui lui a offerte, lui permettant ainsi de réaliser des travaux fructueux et d'arriver aux conclusions énoncées ci-dessus.

Cronaca della cerimonia inaugurale del Congresso Internazionale "Cine- ma e Televisione" di Torino Il Sindaco di Torino Avv. Amedeo Peyron ha ricordato il cammino percorso dal cinema verso il progresso e la per- fezione, dopo gli inizi che proprio a Torino hanno avuto il loro svolgimento.

Proprio nella città subalpina infatti la 'cinematografia italiana è sorta e si è an- data sviluppando ed affermando nel mondo. Ha concluso porgendo a nome della città il benvenuto ai Congressisti italiani e stranieri.

Il Presidente del 2° Salone Internazio- nale della Tecnica Conte Dr. Giancarlo Camerana ha sottolineato la felice colla- borazione tra la Mostra d'Arte cinema- tografica di Venezia e il Salone interna- zionale della Tecnica di Torino. Ha inoltre rilevato come in Europa e in particolare in Italia il conflitto tra la te- levisione e il cinema non sia ancora sorto e ha formulato voti per l'avvenire della televisione e il successo dei lavori del congresso-

Il Presidente del Congresso Ing. Ales- sandro Banfi prendendo lo spunto da quanto detto dal Conte Camerana, an- nuncia che dallo spoglio delle Relazioni presentate al Congresso, risulta l'estremo interesse ai vari problemi tecnici rela- tivi all'utilizzazione della TV per la pro- duzione di film cinematografici e della trasmissione televisiva dei film di nor- male edizione.

La registrazione su film di trasmissioni TV e la produzione di film col metodo televisivo

A. ABRAMSON La relazione passa in rassegna i problemi della registrazione su film cinemato- grafici di spettacoli televisivi.

Esamina altresì la possibilità di produrre film con metodi di registrazione TV.

Le rapport examine le problème de l'enregistrement sur films cinématographique des programmes de télévision.

L'Auteur envisage aussi la possibilité d'une produetion des films par la me- thode de l'enregistrement télévìsif.

This paper reviews the applications of Television film recording and the possi- bilities for applying the editing principle to it.

There is a need in television for a flexibility and perfection that cannot be attained by using live television techni- ques. The means for meeting this need lie within the scope of any television station equipped to record television programs on film. But today's methods of television film recording must be improved both filmically and techni- cally.

Cathode-ray photography dates back to 1938. In that year the first attempts were made to photograph the image on the kinescope tube (1). The low light intensity of the image combined with the use of standard spring-wound ca- meras gave very unsatisfactory results.

The most difficult problem was to syn- chronize the 30-frame/sec rate of the te- levision screen with the 24-frame/sec rate that is standard motion picture practice. Twenty-four frames per sec- ond were necessary in order to use ex- isting projection and sound apparatus.

The most critical characteristic in the recording camera is the timing of the shutter blanking and exposure inter- val (2). This problem has been solved by means of cameras incorporating spe- cially designed mechanical or electronic shutters.

Essentially, a television film recorder consists of this special camera, a monitor which will give precise visual images and a sound recorder to pick up the ac- companying sound. At present there are both 16-mm and 35-mm television film recorders with either single or dou- ble system sound.

Using 16-mm has the advantage of lower film and processing costs; it is approximately one third as expensive as 35-mm. No marked improvement is to be had by recording on 35-mm rather than 16-mm at the present time. With the use of fine-grain, high-resolution, 16-mm film emulsions, no loss of resolu- tion in recording the television image is noticeable. Using 35-mm has the added disadvantage of very stringent fire re- gulations and, finally, the cost of 35- mm projection equipment is often pro- hibitive. As a result, most television stations are using 16-mm film for their recording (3); 35-mm film is being used primarily for theater television.

There are four main purposes for which television film recordings can be made at present:

1. Transcriptions. The transcription is the main function of television film recordings today. It is a recording of a complete show either as it goes over the air or as a closed-circuit operation. It may be shown as: (a) delayed telecast, to make up for the difference in time zones between the east and west coasts;

(b) repeat telecast, to catch a larger audience at a more appropriate time;

or (c) syndicated telecast, in which case it is sent to a station that is not con- nected by either coaxial cable or micro- wave relay, and is shown at any con- venient time.

2. Theater television. Television film recordings are used as an intermediate system of television projection. The program is picked up by receiving equipment at the theater. It is then re- corded by 35-mm single system equip- ment. The signal is inverted and a direct-positive print results. The film is fed into rapid-processing machines where it is processed, dried and fed directly into the projection machine in a little over a minute from the time of exposure. This system allows theaters to show television programs using exi- sting 35-mm projection equipment (4).

3. Research. This includes recordings made for either auditions or previews.

Recordings are often made to improve the quality of a program. Techniques of camera work, acting, lighting, set de- sign and all the elements that go into a television show can be checked before the program is to go on the air.

4. Reference. There is no better way to keep a record of a television program than to record it as it goes over the air.

It is possible that the F.C.C. may re- quire a record kept of every program telecast.

Technically speaking, the quality of television film recording is fairly good and will continue to improve. With certain refinements, such as greater bandwidth and more lines, it should eventually be impossible to distinguish a television film recording from a film shot by a standard motion picture camera.

Dissatisfaction with present television film recording quality has led to the rise of the multicamera motion picture system. In this system a multiple ca-

mera setup utilizing three or more standard motion picture cameras is used.

All cameras can operate simultaneously.

By utilizing live television techniques of dollying and camera movement, the program is covered from a multitude of angles. With the use of an ingenious cuing system the films from the diffe- rent cameras are later spliced together to form a complete television pro- gram (5). The use of multi-camera setups is, of course, not new. They were extensively used some twenty years ago in the early days of sound (6). This system, at present, gives major-studio quality and as such deserves much me- rit. Assuming that eventually the qua- lity of television film recording will equal that of standard motion picture practice, the multicamera system will not maintain its superiority over record- ing through the television camera which has these advantages:

1. The television camera has an enor- mous advantage over the standard mo- tion picture camera, in that all it “sees”

can be viewed instantly. All camera setups can be checked on the monitor for lighting and composition. There is no problem of parallax, focus or ex- posure. The director knows in advance exactly what the scene will look like.

Many a director and cameraman in the major film industry would like to have this tremendous advantage. During the actual performance any mistakes can be seen and immediately reshot. There need be no waiting for " rushes " as there can be no doubt as to the scene's outcome.

2. It allows film to take advantage of the light amplification characteristics of the image orthicon camera. Thus it will be possible to film certain scenes under light conditions that are impos- sible with the standard motion picture camera (7). This means the use of more natural lighting or the use of a mini- mum of lighting equipment.

3. Certain optical effects such as dis- solves, fade-ins, fade-outs, double ex- posures and background shots can be made in the television cameras them- selves. This adds to the economy of the system as it can reduce the cost of pro- ducing these special effects optically.

4. It allows the television station to utilize the equipment on hand. Thus the television camera can serve a dual purpose. It can be used for live tele- vision programs or it can be used in conjunction with the television film re- corder. This allows the station com- plete control over program content as all programs can be made on the studio premises and conform to the station's needs.

5. Since all recording is accomplished at a central point, it should be easy to keep the recording and developing proc- ess under the strictest possible control.

The potentialities of a system like this are unlimited and may make the stand- ard motion picture camera as we know it today obsolete.

Filmically speaking, the present-day television film recording leaves much to be desired. It possesses the physical characteristics of motion picture film

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Ordre du jour adopté à la clôture du Congrès International de la Techni- que Cinématographique “Cinéma et Télévision” de Turin.

A la clôture du IIIe Congrès Interna- tional « Cinéma et Télévision » qui s'est tenu à Turin du 6 au 9 octobre 1952, les 29 délégués des Unions et des Asso- ciations nationales et étrangères intéres- sées à l'industrie et à l'exploitation du Cinéma et de la Télévision adoptent l'ordre du jour suivant:

ORDRE DU JOUR:

Considérant que:

a) Parmi les cinq sujets proposés à l'étude du Congrès, les communications faites ont été particulièrement nombreu- ses dans le domaine des rapports entre Cinéma et Télévision;

b) Que ces communications ont clai- rement mis en évidence les différents aspects techniques et industriels de ces questions ;

c) Le problème technique et artisti- que de l'utilisation des films cinémato- graphiques pour la transmission par té- lévision a été largement discuté;

d) Qu'une technique nouvelle de la production de films cinématographiques, désignée sous le nom de « film électroni- que », prend un intérêt particulier dans le domaine pratique;

e) Que la technique de la transmis- sion par télévision des films cinémato- graphiques a, d'autre parte, été large- ment discutée;

Le Congrès prend acte :

1° Des remarquables résultats techni- ques obtenus dans les secteurs ci-dessus mentionnés ;

2° Du fait que la composition des pro- grammes de télévision exige une utilisa- tion importante de films réalisés pour leurs exigences techniques et artistiques particulières ;

3° Du grand rôle que pourront jouer les projections sur grand écran pour une forme particulière de programme;

4° Du fait que le Cinéma et la Télé- vision ne sont pas essentiellement oppo- sés, et qu'une collaboration possible et effective pourrait être réalisée par des accords concrets.

Emet le vœu:

1) Qu'il soit procédé à l'établissement de normes qui précisent les caractères techniques que devront posséder les films pour télévision;

2) Qu'il soit procédé à une unification des normes électriques et photométrîques {y compris « les chiffrés d'épreuves » à projeter) des projecteurs de télévision sur grand écran;

3) Que l'opportunité de créer un type spécial de norme de transmission par té- lévision réservé à la télévision dans les salles cinématographiques ci-dessus men- tionnée soit examinée.

Convaincu que, dans l'intérêt du pu- blic lui-même, il ne soit possible de développer la télévision de la façon la plus efficace que par la collaboration de l'industrie, le Congrès prend acte de la motion présentée par l'Union Internatio- nale des Exploitants cinématographiques et la Fédération Internationale des Pro- ducteurs de Films annexée au présent ordre du jour.

Le Congrès exprime enfine sa vive gra- titude au Salon International de la Tech-

IL FILM PER T E L E V I S I O N E

ALESSANDRO BANFI

La tendenza attuale delle programma- zioni televisive è quella di dare sempre più la preferenza alle trasmissioni di film. E ciò va inteso, sia come utilizza- zione di film spettacolari già in circola- zione nei circuiti di proiezione, che sotto l'aspetto di una speciale produ- zione di film unicamente dedicati alla televisione: i cosidetti «film TV ».

In quest'ultima categoria di film, si possono anche includere quei « noti- ziari » giornalieri o bi-tri settimanali (telegiornale, journal télévisé, news reel) che vengono prodotti da appositi ser- vizi cinegiornalistici espressamente orga- nizzati dalle Società di trasmissione te- levisiva.

La tendenza ora accennata della sem- pre maggiore preferenza del film nelle trasmissioni TV è giustificata da diverse considerazioni di carattere tecnico-eco- nomico. Anzitutto la tecnica degli ana- lizzatori TV di film (talvolta chiamati

« telecinema ») si è molto perfezionata ad affinata, tanto da superare come ri- sultato « medio » in ricezione (conside- rando quindi tutta la catena TV dall'ana- lisi alla riproduzione sullo schermo ri- avente del telespettatore) la qualità nelle riprese dirette con le telecamere.

Infatti i più recenti dispositivi analizza-

tori per trasmissione TV di film, quelli particolarmente del tipo cosidetto

« flying spot » consentono di ottenere facilmente una correzione automatica (o manuale) continua del « gamma » glo- bale di tutta la catena di trasmissione TV, nella presunzione di un « gamma » medio di 2 ÷ 3 sullo schermo catodico ricevente, cosa difficilmente realizzabile con altrettanta facilità e continuità nelle riprese dirette.

La finezza di analisi dell'analizzatore tipo « flying spot », se vengono osservati particolari accorgimenti tecnici, è poi decisamente superiore a quella fornita dalle telecamere in ripresa diretta, e non è come in talune di queste ultime (ad es. l'image orthicon) forzatamente limi- tata da fattori tecnici funzionali.

Partendo da considerazioni stretta- mente economiche si potrebbe anzi giun- gere alla conclusione che la registrazione preventiva di un film dei programmi TV sia estremamente opportuna per l'esercizio televisivo.

Occorre però chiarire che non si tratta qui di una normale ripresa cinematogra- fica del programma da trasmettersi, cosa che porterebbe forzatamente ad un

« handicap » tecnico per la qualità della trasmissione TV, per le ragioni che ver-

ranno illustrate più avanti e che costi- tuiscono l'essenza di questo scritto, ma bensì di un film ottenuto registrando, fotografando, l'immagine di uno schermo TV ottenuto da una ripresa con camere TV funzionanti su uno « standard » ad altissima qualità.

Questo procedimento che a prima vista potrebbe apparire circonvoluto ed inutilmente complicato presenta al con- trario, parecchi, notevoli vantaggi tec- nici ed economici.

1) Anzitutto le varie scene dell'azione del programma da trasmettersi sono via via registrate a distanza di tempo, senza l'assillo della continuità e del legamento immediato, successivo, previsto dalla sceneggiatura e dalla regia. La produ- zione risulta così meno costosa per la maggiore comodità delle riprese, dispo- nibilità degli attori e riduzione di com- pensi straordinari ai tecnici e maestranze sceniche.

2) Il film ricavato presenta tutte quelle caratteristiche tecniche fotografi- che (densità, gamma, contrasti, ecc.) in- dispensabili per una buona trasmissione TV e delle quali verrà trattato più avanti.

3) La ripresa del film in queste con- dizioni, cioè pel tramite di apparecchia- ture TV, è grandemente facilitata e snel- lita nei rispetti di una normale ripresa cinematografica, per la possibilità di controllo immediato e continuo da parte del regista delle scene filmate, e del loro « montaggio » istantaneo ottenuto attraverso il complesso di ripresa TV a 3 o 4 camere mixabili, in funzione con- temporanee nello « studio ».

4) Il maggior sfruttamento e valo- rizzazione di una produzione televisiva e costosa che, se non registrata su film, viene totalmente perduta dopo la tra- smissione televisiva, senza lasciare al- cuna traccia: la registrazione su film, effettuata in modo tecnicamente adatto per la TV, consentirà di rimettere in onda in qualsiasi momento, quella pro- duzione, nonchè di effettuarne commer- cio o scambio con Società del broadca- sting TV internazionale.

5) La qualità tecnica ed artistica della trasmissione non potrà che miglio- rare, considerando le maggiori possibi- lità ed elasticità di controllo, e di sele- zione delle riprese, diluite in un mag- giore lasso di tempo non più obbligato, nonchè della possibilità di ripetizione delle scene imperfette o poco riuscite per qualsiasi causa.

La registrazione diretta di un pro- gramma TV fotografandolo « is et sim- plicitur » da uno schermo di ricevitore televisivo, non dà però garanzie di suffi- ciente qualità ai fini delle considerazioni or ora esposte, se la trasmissione viene effettuata sugli « standard TV » attual- mente in uso. In modo particolare gli

« standard » europei con 50 immagini/

secondo, presentano la difficoltà del tempo brevissimo e per lo più insuffi- ciente in pratica (per le caratteristiche meccaniche delle normali camere da presa cinematografiche) di passaggio da un fotogramma all'altro successivo.

Quest'ultimo inconveniente non si pre-

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but lacks the inherent capabilities of the true motion picture, for it is restricted by the limitations of the live television program.

In a live television program a unity of time and space must be observed.

Movement is confined by the physical limits of the stage itself. Performers must learn complete scripts. Changes in costume or makeup take time and there must be cover-up action during this period. Even when using two or more sets the performer can travel through them only at a certain speed.

Transitions must either be eliminated or filmed in advance. Outdoor sets are seldom if ever used. During the per- formance any mistake is easily noticed and there is no chance to rectify it.

As a result of these restrictions, the average television play today resembles a stage play in that the story is advan- ced through the dialog. This is good stage technique, but is poor television.

Television is a visual medium and as such the story could and should be advanced by visual means. Movement on the screen is interesting and tells its own story. Dialog is important but should never dominate the picture.

Editing

The true motion picture is not just a recording of reality but a rearrangement of that reality to suit its own purposes.

Both the standard motion picture ca- mera and the television film recorder are recording mechanisms. They can do nothing but record on film a scene that is placed before their lenses. Then how does the motion picture gain its flexibility and freedom of movement, its ability to manipulate time and space?

The answer lies in the editing process.

It is in the editing room that the motion picture, as we know it, comes into being.

Here is created filmic time and filmic space. Filmic time and filmic space exist only on the individual strips of motion picture film. Actual events can be stretched or compressed. Time can be made to stand still or to go forward or backward. It is possible to show events, occurring at widely separated points, and simultaneously. Unrelated shots are cut together and meaning is extracted from tbeir juxtaposition. An accident occurs; we see, in rapid suc- cession, the victim crossing the street, the driver's grim look, his foot slam on the brake, the victim's horrified face, the wheels skidding on the pavement, the victim lying in the street. A man steps out of a New York hotel into a South American street. These and many other scenes are possible only through the editing process. These are no mere tricks, they are the lifeblood of the visual medium. As a visual medium, television can use the editing principle to its advantage. This will free tele- vision from the limitations imposed upon it by live television techniques.

At the present time, the major net works are editing television film record- ings for the following reasons:

1. To make transitions which would otherwise be impossible if the program were recorded straight through.

2. To rerecord imperfect scenes.

3. To eliminate excess footage and edit the show down to required length.

In applying the editing principle to television film recording, it is well to note a major difference between the motion picture and television. Both, being visual mediums, have the shot as their foundation. However, the motion picture is filmed on a single-shot basis whereas television is set up on a mul- tiple-shot basis. This is no handicap;

quite the contrary, it can be used to great advantage.

In the motion picture each individual shot is arranged for maximum effect.

There is always one certain camera angle that will be most effective de- pending upon what idea is being con- veyed to the audience. Thus each scene is carefully arranged to put across this idea. Therefore, even the same scene when photographed from different angles will be rearranged to suit each individual shot even though all of these shots will be cut together to create a coomingly continuous scene.

This is not necessary in television, tor the use of multiple cameras combined with electronic cutting makes it possible to get a variety of shots without making new setups for each individual shot.

This can be done by careful planning of camera angles, the use of proper focal lenght lenses and the use of lighting to suit the scene. Here, of course, the maximum effect from each shot or cut is not as assured as in the single-shot setup, but such should be nearly attained.

Thus it is possible to create a maximum number of shots with a minimum num- ber of setups for any given scene. It is proposed to use this type of multica- mera setup wherever the action will allow it.

In order to apply the editing prin- ciple to television film recording, pre- production planning is the first neces- sity. In addition to planning details of sets, costumes, props, etc., the script must be broken down into two types of sequences. The first type of se- quence should consist of that kind of scene where two or more television ca- meras can be used for the necessary va- riety of shots. This type of scene will be recorded as a unit making full use of electronic cutting.

The second type of sequence should consist of that kind of scene where it is necessary to stop the recorder to make changes in lighting, costumes, sets, makeup, etc. This can be recorded with a multi-camera setup or, if circumstan- ces demand, with only one camera.

In all instances, the various sequences will he recorded in whatever order is most practical. By minute scheduling of operations it should be possible to record the various sequences in the shortest amount of time. After proc- essing, the recorded sequences can then be edited into a smooth, flexible program with a minimum of time and effort.

The cost should approximate straight television film recording with the qua- lity equaling that of professional mo- tion picture practice.

This is a process in which we are utilizing the best features of motion

pictures and television. We have given the television camera a memory. We have taken the unique picture-control elements of the television camera and added the permanency, flexibility and perfection of motion picture film. Thus the process is one that is peculiar to neither motion pictures nor television alone, but is a synthesis of the two that can be used to their mutual advantage.

It has been said that television will lose its sense of " immediacy " through the use of television film recordings.

It has also been said that the public likes to know that the program being telecast is being presented at that very moment. This all depends upon the type of program being considered.

Every day millions of persons attend motion pictures that are from nine to twelve months old before being released.

Even the earliest " newsreels " are from a few days to several months old when being presented.

" Immediacy " is determined by pro- gram content. Obviously, no other me- dium is as well equipped to present an event as it actually happens as televi- sion. In reporting spot news, sport events, presidential elections and other events of great public interest, television can present these programs to the public as they actually occur. To this list can be added programs of a semirehearsed nature such as vaudeville, comedy or variety shows. However, rehearsed programs, especially drama of all va- rieties, need the perfection and flexibi- lity that only a filmic use of the tele- vision film recorder can give them.

There is no reason why drama should be presented live. The perfection and flexibility that can be had by this me- thod mean better dramatic programs and that is our ultimate goal.

This is where the future of television film recording lies and it doesn't inter- fere with any type of program in which

" immediacy " is its most important aspect. To the contrary, it can record those programs of lasting interest and preserve them for posterity.

References

1. R. M. FRASER, Motion picture photog- raphy of television images, «RCA Rev. », vol. 9, pp. 202-217, June 1948.

2. THOMAS T. GOLDSMITH, JR. and HARRY C. MILHOLLAND, Television transcrip- tion, « Electronics », vol. 21, pp. 68- 71, Oct. 1948.

3. Report of the Television Committee, Films in television, « Jour. SMPE », vol. 52, pp. 363-383, Apr. 1949.

4. RICHARD HODGSON, Theatre television system, « Jour. SMPE», vol. 52, pp. 540-548, May 1949.

5. JERRY FAIRBANKS, Motion picture pro- duction for television, « Jour. SMP- TE », vol. 55, pp. 567-575, Dec. 1950.

6. F. GREEN, The Film Finds its Ton- gue, p. 67, G. P. Putnam, New York, 1929.

7. THOMAS T. GOLDSMITH, JR. and HARRY C. MILHOLLAND, Television transcrip tion by motion picture film, « Jour SMPE », vol. 51, pp. 107-117, Aug 1948.

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Dopo aver considerato le caratteristiche funzionali di una catena di trasmissioni- ricezione televisiva, l'Autore giunge alla conclusione che la « dinamica » luminosa dell'intera catena, dalla camera da presa al tubo catodico ricevente, non può ecce- dere oltre uno scarto da 1a 50 nella gamma dei contrasti dell'illuminazione delle scene da trasmettersi.

Nella generalità dei film cinematografici di produzione normale la « dinamica » dei contrasti fotografici raggiunge il valore di 1/100 sino a 1/150, e pertanto nella trasmissione TV di tali film pel tramite di analizzatori sia del tipo ad iconoscopio o photicon, che del tipo « flying spot », si rende necessaria una « compressione » di tale dinamica per riportarla entro la gamma dei valori tollerati dalla trasmis- sione TV.

L'Autore esamina i sistemi possibili per realizzare la « compressione » della di- namica luminosa sia su film normali del commercio che nell'esecuzione di film speciali per televisione.

Après avoir examiné les characteristiques jonctionelles d'une chaîne complete de TV, l'Auteur arrivé à la conclusion que la « dynamique » lumineuse de cette chaîne, de la camera de prise de vue au tube cathodique récepteur, ne peut aller au dela d'un écart de 1 à 50 dans la gamme des contrastes de la brillance des éléments des scenes en transmission.

Dans la généralité des films cinéma-photographiques de production normale, la

« dinamique » des contrastes photographiques, atteint la valeur de 1 à 100 jusqu'à 1:150; pourtant dans la transmission TV de ces films moyennant des analyseur soit du type à iconoscope ou photicon, soit du type « flying spot » il sera nécessaire réaliser une compression de cette dynamique pour la réduire entre la gamme des valeurs tolérées par la transmission TV.

L'Auteur examine les systèmes possibles pour réaliser la compression de la dynamique lumineuse soit sur films normaux du commerce, soit dans l'execution des films spéciaux pour télévision.

After having considered the operating characteristics of a television chain, the report concludes that the « dynamic » contrast of a TV transmission cannot exceed the max. figure of 1/50.

Assumed that the dynamic contrast of a commercial film, extends over, from 1/100 up to 1/150, it appears absolutely necessary to introduce a « compression » on that dynamic contrast, in order to obtain a good television transmission of the same film.

The Author examines all the possible systems to accomplish this requirement, both on existing commercial films and on the making of special films for television broadcast.