The tempo - speed of a kinetic flow

6. THE TEMPO - THE SPEED OF A KINETIC FLOW

St Augustine, Confessions, book XI

Tempo is one of the essential elements of film expression and that is why determining its precise and special qualities must be considered important.

As to this aspect of the film kinetics we should also start from examining a normal human motion under normal circumstances which, as it has already been said, takes 2/3-3/4 of a second or around 80 - 90 MM (metronome beats per mi­nute), which stands for average human speed.

As well as his own time and space perspectives, Man also has his own perspective of the tempo of the motion within this space and time.

A basis for determining the scale of the tempo can be found in Man's nature and his disposition to move at a speed that fits him best. The tempo is related to the speed at which a human organism is functioning and it is conditioned by and subject to his physiological, anatomical and psychological features.

Herbert von Karajan used to express an opinion that amongst the more impor­tant conditions underlying his successful work were his heart beats, exceptionally regular. While conducting he felt that any disturbances in his heart functioning might result in his being internally desynchronized and as an interfering factor it might affect the way he was conducting his orchestra. Karajan also remembers listening to one of his recordings while he was out in the mountains. He noticed that with the change of air pressure the tempo fixed in the studio seemed to him much slower. It means that the feeling of the tempo varies, as everything in art, and is connected with the mood and pulsating of the organism. The basis for every musical or film theme interpretation lies in the choice of the tempo.

One should remember that the tempo is of highly subjective and zonal character. The first question that comes to one's mind is - what sort of unit is good for determining the tempo, i.e. by what motion unit all various phenomena that make up the film are going to be measured. For this one should have on hand a convenient reference point that might be easy to define. In any film this base time is called a base metric modulus to which reference has already been made in this paper. It is a virtual, precisely adjusted motion unit at an elemental motion level. In order to determine a tempo we usually use a metric unit which defines a regular motion progress in time. The metric unit is designed in principle to keep the motion at a medium tempo, because one can feel the difference between rhythms of this tempo. (To measure all permanent phenomena it seems that medium values are the best, that is such values that can be divided at will into proportionately smaller or grouped into proportionally bigger ones). As a matter of fact, the sca­le of a tempo differentiation is relatively narrow. As the fast tempo is gradually fading out, soon there is a limit reached beyond which the direct measure is no longer useful and it is than that the direct measure of the tempo must be employed. Fast motions join together to form groups of bigger units and these are usually medium tempos (around 80 MM). As for slow motions, the motion units split into combined groups (e.g., a take), which again result in metric units of a medium tempo. This can be illustrated with an example of a man stepping at an even pace (a classic metric unit). No man is, however, able to shorten or lengthen (i.e. accelerate or slow down) his steps ad infinitum. The motions that are too fast tend to combine automatically into bigger metric - rhythmic units (most frequently into the ones of a medium tempo), and those that are too slow ones split spontaneously into a certain number of metric units (steps or motions) in order to give an impression of rhythm, its function and its meaning.

6.1. EXTERNAL TEMPO

ND

By taking 18 frames (3/4 sec) for a basic metric modulus we have received a base for a precise adjustment and determination of the tempo.

A film that is arranged according to the metric unit can be said to be "step­ping" regularly at a given tempo, faster or slower, which depends on the density (frequency) of accents. The tempo is thus defined by steady pulsations of the ac-cents in time. The given duration of a metric unit, i.e. the duration of each of the same "steps", takes, scenes or episodes is determined by an external tempo. In this aspect the tempo must be understood as an absolute duration of a motion unit. This strict definition is only partly justified - as an attempt at translating the human perception of time into a form of numbers and accurate quantities. The lon­ger the "steps" are, the slower the tempo is and vice versa - the shorter the regular "steps", the faster the tempo.

The external tempo or the motion speed of a given take, sequence, film phrase or a longer section of a film depends on a number of metric units belonging to a given division of time, or put in a different way, on the length of a regular me­tric unit ("a step").

It is quite obvious that a precise external tempo can only be characteristic of the films whose metric units are defined and adjusted. All the other time and spa­ce values are proportionately related to metric units. They overlap if they are of the same values; when they are smaller they multiply a certain number of times; in case they are bigger they become differentiated with the help of those units. Owing to this, a film is flowing ahead at a precisely determined and regular speed. Of course, there is a possibility of rejecting regular metric "step" as it frequently happens in films and sometimes in music (e.g. free jazz).

If a film has no metric arrangements, i.e. when its duration is made up of disproportionate motions that cannot be translated into any determined units of du­ration, then there is no precisely determined external tempo (which is the regular speed of the motion progress in time which is a specific feature of expressing its time arrangements).

Metrically arranged kinetic flow in its external (kinetic) aspect is moving for-ward, evenly irrespective of the length of motions or takes. Through the motions or takes that are twice shorter it is moving during the time which is half shorter, and through those that are twice longer, during the time twice longer than the base modulus. It is flowing in a similar way through other time values. That is why we can say that short motions or takes are "faster" than the long ones, because shorter motions last shorter, i.e. they are flowing faster filling a given division of time. The stream of kinetic arrangement of a film is in principle in a given mo­tion, a take, a scene or even a sequence of the same speed, i.e. of the same external tempo. In motions or takes of some defined length it is the same as in shorter ones, only their duration is shorter; the same is time of the longer ones. It is essential that metric pulsation be harmonious. This refers, of course, only to the steady tempo where there is neither accelerando nor ritartando nor any other agogic variations. Thus the external tempo in any film depends upon the speed (length) of single "kinetic step" (module), i.e. not on the speed (length) of the sin­gle kinetic elements or agogic deviations.

Metronomic values give an exact determination of a film tempo. A careful lo-ok at the scale shows that the scale of the tempo is of logarithmic nature as much the same as, e.g., the scale of rhythmic times or the other scales.

The Weber - Fechner laws also valid for the tempo says that the force of impressions is growing proportionately to the logarithm of a stimulus:

W = c log p. The metronomic scale is designed on the basis of the above mentioned law.

If we assume that a medium tempo amounts to 60 - 80 MM, then the measure of the fast ones will be 120-160 (60-80 x 2), and of the slow ones 30¹ - 40 MM (60 - 80: 2). From this we get metronomic "octaves", each of which is internally divided into 16 unevenly marked degrees.

"But we still have not got any exact measure of time, as it may be that even a shorter poem recited languidly may be heard longer than a long poem but said faster".

Thus, the tempo must be considered to be relative. It is only conditions and circumstances that tell us which is a genuine tempo and which is not. It is important to remember that feeling of the tempo is as much psychological as physical factor. The psychological tempo also depends upon what fills the time - how many patterns are created within the given duration of a metric unit, and not only upon the length of time and the mobility of a rhythmic aspect (the term rhythmic aspect is used here for rhythm expressed in concrete time values - certain forms and patterns). In music rhythmic patterns are called "rhythms" e.g., for a waltz, a samba, a polonaise etc.

6.2. INTERNAL TEMPO (mobility, kinaesthesia)

Aristoteles

The internal tempo is the frequency of the applied values of motion duration and is formed in various ways within the existent external tempo. It depends on a number of single motions which one can see when watching a certain movement within a given period of time. One should see a difference between the mo­bility and the external tempo, as much misunderstanding and unclear definitions arise out of these two concepts being mixed up. By deliberate editing a sequence of short takes we can produce an effect of a faster tempo but, as a matter of fact, this cannot be fully created by editing alone. "Short" editing can give an effect of a fast tempo, but principally it generates a bit different phenomenon, the phenomenon of "m o b i l i t y" or internal tempo. It results in considerable differences in relation to the real tempo. Small elements of a motion create a greater internal tempo although the base metric "step" is identical as in longer movements whe­re the tempo seems slower.

Ti = (nxM)

k

Ti - Internal tempo, mobility, kinaesthesia

n - a number of successive motion

M - metronomic value

k - a number of metric units

The mobility (Ti) is identical with the tempo indicator M (metronomic value), if the number of motions (n) is the same as the metronomic units (k). The inter­nal tempo indicator (Ti) is smaller, identical with or bigger than the metronomic indicator (M), if the number of motions (n) is bigger, identical with or smaller than the number of metric units (k).

The mobility tends to vary within the existent external tempo. Seeing the difference between the tempo and the mobility is very important from an artistic po­int of view, as these two motion aspects are of different kinetic character. When the movement is observed from the aspect of a greater or lesser speed (a tempo), its expression is different from that observed from a greater or lesser mobility (ki­naesthesia). When, for instance, a movement is in fast tempo, or when the camera is moving very fast, this may express nervousness, tension, decisiveness, anxiety, etc. The mobility (the speed or the number of motions within a time unit - a modulus) may express something different - lightness, gaiety, comicality itd. Of course, the medium of expression is not exclusively the tempo or the mobility -they go side by side with and are integrated into other elements of expression: articulation, facture, rhythm, dynamics, action line, etc.

Various aspects of the tempo are not interchangeable in their function and meaning. Accelerated shots (mobility) are perceived, for instance, as deformation of time, but this may create a certain degree of comicality or give some other characteristics of the world on the screen, while the speeding up of actors' function (mobility) gives characteristic features of a given person and his psychic state.

The actual tempo of a film seems to be a motion not only in time (as in mu­sic, for instance) but in space as well. The film time units - modular values - determine the tempo in its time and space perspective as much the same as some ot­her kinetic aspects of a film.

6. 3. REAL TEMPO

Andrej Tarkowski

Thus, the tempo depends on what basic speed a director will choose as good for a given frame, a scene or a sequence. The most important thing is to continue the same tempo throughout the takes that show a certain action, scene or sequen­ce, since on this the uniformity of the whole structure depends to a great degree. Practical wisdom says that it is impossible to put two takes together in an uninterrupted way unless their tempos are adjusted to each other. Because takes can be made at different times and in different places, there is often a problem of connecting them together which arises out of their disharmonious tempos. This is further complicated by the fact that the tempo is affected by both the size of the plan, the position of the camera, they type of lens (wide or narrow), type of topography (plane or depth one), horizontal or vertical change of the angle, etc. It is only the small change in one of the said elements, for instance in the plan or an­gle in relation to the axis of action or optic axis of the lens that produces entirely different effect of the tempo.

The basic condition of a harmonious combination of motions is keeping up the effect of the same tempo. When there is a close-up, objects seem to move for-ward much more speedily that they do in a general plan, because in a close-up changes of positions are perceived much more intensely owing to their relation to the edge of a frame which, for our perception, is the surest reference point. A speed effect (the effect of the tempo) in a film may depend, for example, on the size of an object. A big object moves forward more slowly than a small one, and a smaller plan surrounding a moving object gives an effect of a faster speed. Therefore, when making close shots one must remember that a motion should be ma­de more slowly than same one made in wider plans so that it might be spliced with the same motion. Only in such case do we have an impression of the same tempo of their movement in each of frames or in the whole sequence.

The tempo, may be slowed down by means of a slow-moving camera and panoramic shots especially in a general plan as well as by meaning of dissolving views; it may be accelerated by speeding up a moving camera, whip-pan shots, pa­noramic views and by reducing the number of frames per second while making a film. The tempo may also be changed when editing a film by shortening (spee­ding up the tempo) or lengthening (slowing down) the normal film modulus ma­de up of assumed 18 frames per second.

The real tempo (the general impression of the tempo) in a film may be adjusted in several ways:

- by increasing or reducing the number of frames per unit of time (slowing

down or speeding up a motion);

- by longer or shorter metric modulus. The value of the modulus of a given film episode should be determined in advance and according to these fixed values, the tempo of the action of the film should be pushed along;

- by a movement of a frame (the camera). The speed of this movement may be adjusted by strengthening or weakening of accentuated points, that is by the frequency of accents produced by the movement of the frame;

- by a motion in a take. The motion and in it - clear and dynamic moments preferably of the main character or a major object in a take may be adjusted so as to fit best the very emotion of the situation expressed through the tempo of that motion. Of special importance for the effect of the tempo is the direction of the motion in relation to the camera and the width of the lens. The wider the lens is with the direction being closer to a vertical one to the camera, the grater the tem­po of the motion;

- by greater or lesser length of takes the film motion can be tightened or loosened. Shorter takes are "thicker" and the longer ones are "thinner" owing to the greater density of accents in the first case (the beginning of takes) and lesser one in the other.

It seems necessary to explain yet another concept directly related to the concept of the tempo, which may play a very important role in the film time. This concept is called agogics.

A g o g i c s means modifying, internally varying the tempo. It is different from mobility and external tempo in its being irregular, breaking established pat-terns (metric and rhythmic ones). It is a direct mode of expression. Agogic deviations in a film can be most frequently seen within the motion in a take or the motions of a take. In most cases cuts can be very precisely adjusted. This does not mean, however, that in this type of the motion (the editing one) we cannot make use of agogic modulations for an expressive function. We do not consider those changes in a picture or a sound to be a violation of an order. The agogic deviations introduce liveliness into a regularly arranged flow of the film and may be a few times greater than the normal tempo at which a film is moving on (even 1:4).

All these speeding-ups and slowing-downs which function within a film mo­tion as a normal state of affairs are exactly mutually compensated by the effect of a regular metric film modulus. This results in a slow but accurate, metric pulsation re-echoing throughout the whole film work.

As it has already been said, to get an effect of a speed the editing "mobility" has a role to play, i.e. the length of takes as well as the mobility of characters and objects photographed. It must be underlined once again that the external tempo need not be fast if the takes are short, as this aspect of the tempo depends, first of all, on a fixed metric unit. Mobility (internal tempo) is enhanced, because shor­ter takes come up at a higher frequency of changes and produce an effect of a gre­ater mobility of the film kinetics. Accents (the beginnings of takes) are therefore more densely spread.

Faster tempo gives an effect of a more intense, lively motion and grater mo­bility while a slow tempo has smaller mobility (the former has more kinetic unit per time unit fixed at will). In a mild tempo the long, slow and smooth movements are more useful than the short ones which repeat themselves. It is quite the opposite in the fast tempo. The mobility (the internal tempo) is thus the element of the tempo, but they do not overlap completely. Internal tempo changes drastically the perception of the tempo due to the change in the degree of mobility. To enhance the external tempo through mobility, strongly fragmented motions sho­uld be contrasted with the long ones. It may sound paradoxically, but time in film is most dense when there is no movement because dense discontinuity transforms into the homogeneous continuity.

The conclusion that can be drawn from above considerations is that the effect of a tempo results from complex and multi-layer structure. They are made up of the sizes of motion units and metric units, their internal mobility (this in turn de­pends on the scale of fragmentation and relations to the motions in other layer, etc.). This can be enlarged by superior metric units (e.g. takes or bigger units, if they can be perceived) as well as sizes and degree of the variability of a phrase or a sequence. Only against the background of complete facture[1] arrangements, one can see the qualities of the tempo of a film.

Finally, for the sake of illustration of the above, let's compare the kinetic arrangement of a film to a man who is walking to the beat of a march and at the sa­me time with his hands, his trunk and his head he is making a variety of motions, synchronized and harmonized with the motions of his legs.

The m e t r e is a regular step in a two-part time. The t e m p o is a speed at which it moves on, the m o b i l i t y means small motions of the head, the trunk and the hand. The r h y t h m is understood to be its complete gesticulation synchronized and harmonized with the duple measure and the speed of the motion. The a g o g i c s is produced by the slowing down or speeding up of the mo­tions within a regular metric step. Seen as a whole, this kinetics should be characterized by its own order and expression, making up a definite kinesthetic phenomenon of the film.