Title

A Play of Light

This paper was presented at the Showlight 2001 conference in Edinburgh, on 23rd May 2001.

The Search for Inspiration

Lighting for the theatre is a comparatively young art, with lighting design only becoming a recognised, specialist discipline around fifty years ago. In particular, the control of light in performance has been limited in its sophistication by the technology available. The arrival (from the 1970's onwards) of computerised systems means that rather than asking the question "how can we control our lighting?" we are now able to ask "how do we want to control our lighting?".

However, looking at the current developments in lighting control suggests that change tends to be evolutionary not revolutionary, with many concepts rooted in a past when lighting controls were heavily constrained by technology. So where might we look for inspiration and guidance for such change? Comparison with other, older performance forms such as music may offer useful insights.

Visit the lighting control room of a theatre during a performance of a musical, opera or ballet, and watch the lighting operator at work. For the most part, he or she will be cued by the stage manager either by cue-light or verbally via headsets, or both. In response to the cue, the lighting operator presses the "go" button - and that's it. Meanwhile in the orchestra pit, things are very different: whenever music is being played, the musicians are either watching the performers on stage, looking at the other musicians or conductor, or following the score. Why are the musicians so much more engaged with the live performance compared to the lighting operator? Could the musicians' approach have something to offer the performance of lighting? Might it be useful to compare light and music?

Light & Music

That there should be a relationship between light and music seems natural, almost instinctive. It is built into our language: words such as colour, brilliance, tone, and chromatic are used in relation to both music and light. Considering light as part of a stage performance, and comparing it with music, we can see strong similarities.

Both exist in time

Theatrical performance (and hence stage lighting) and music both have a time dimension; unlike, say, painting or sculpture. Furthermore, they are both defined in time; that is, they have a limited duration. This leads them both to have the potential for narrative structure or the development of themes and ideas, since they can present their material in a predetermined order. This contrasts with arts such as painting where the artist has little control over the order in which the elements of the work are experienced. For music and lighting, then, dynamics are important; that is, the relationship between what the audience is experiencing now and what it experienced before and what it will experience next.

Lighting designers will be familiar with the experience of watching a rehearsal and knowing that a lighting cue is needed, without necessarily knowing what the cue should do. The nature of the change is less important than the fact of change.

Both are live

Richard Eyre has described theatre as the "art of the present tense". Stage lighting, like the performance that it is a part of, is live, created afresh in front of the audience each time. This "liveness" is the feature of theatre that distinguishes it from drama on film or television. So what is so special about a live performance?

Responding to other performers

Firstly, if all the performance elements are live, then they are free to interact. The members of a band or orchestra may be lead by a conductor, but they listen to each other, responding to the music as it is being made. It is hard to say exactly what effect this has, but that it has an effect is undeniable. Once the technology allowed it, classical music went through a phase of recording large orchestral works in many takes, editing and reconstructing the performance afterwards. This allows errors to be eliminated, creating the "perfect" performance, but the result has a clinical, manufactured quality. The tendency now is to record in as few takes as possible, and to leave in minor errors for the sake of continuity and a sense of real musicians making music together.

The same is true of other music forms; in rock, jazz, pop, etc., live albums are still enthusiastically bought even though they rarely equal the studio equivalents for technical quality. To the listener it is more important to feel the atmosphere of the live event than it is to avoid every little slip or glitch.

If this is true in music, why in the theatre do we insist on adding pre-recorded lighting to the live performance of the actors?

Serendipity

There is a second aspect to the question of what is special about live performance: chance. When we create something live, there is always the possibility that it will go wrong, that disaster can strike at any moment. The theatre audience knows this, and I believe relishes it. Part of the pleasure in watching a performance is enjoying the skill with which it is done: we enjoy good acting or good musicianship as much as we enjoy the performance that is given. Part of the skill is in taking risks and, despite them, succeeding.

And not just succeeding: there is the possibility that the performance will go beyond success; that the elements of the performance will sometimes come together and "click", with all the pieces combining to form a transcendent whole. If we insist on our lighting being pre-recorded, then we cut ourselves of from this happy chance, from serendipity.

How lighting controls must change

If we accept, as I believe we must, that lighting operation should return to being more "live", then how can our lighting controls allow this?

It is interesting to compare a typical musical instrument and a typical lighting playback system.

The keyboard has been a common interface for musical instruments for centuries. With eighty plus keys and two pedals, a piano keeps ten fingers and two feet fully occupied, and an organ may offer substantially more controls all of which are available simultaneously. And of course, a band or orchestra may contain many musicians, each with their instrument.

Compare this with a theatre lighting desk; while a large number of controls are available in theory, in practice the number used is one - the "Go" button.

We must develop lighting controls that can use the full capabilities of the operator to manipulate the lighting in complex and subtle ways in real time.

Automatic and manual

Of course, some lighting changes clearly benefit from fully automated operation; a fifteen-minute sunset cue for example. Lighting controls must allow both manual and a range of "computer assisted" modes. For example, we might have several playbacks, each of which can be run in full manual mode or automatic with various types of override.

These facilities are available on existing lighting desks, but they are often so poorly implemented that it is clear that the designers do not really expect anyone to run cues in anything other than "Go Button" mode. Manual faders are positioned such that the operator cannot get their hands to them without the risk of pressing various other buttons. Cheap faders are not smooth or provide insufficient resistance to movement, making jerky fades inevitable. Some desks even require you to press the "Go" button to load a manual cue onto the faders.

What we need is a desk with multiple playbacks of different kinds. Nearest to what we are familiar with would be the "Go Button" playback, but with an override available for the cue time in the form of a centre-sprung lever, similar to the pitch-bend controls found on electronic keyboards.

Next might be a classic manual cross fade playback, with two faders of the quadrant pattern that used to be found on Strand desks such as MMS. Micro switches at the start and end of the fader's travel tell the desk when the cue starts and ends, but just as importantly, they give audible feedback to the operator. Remember that the operator will not be looking at the position of the faders, but at the light on stage. The faders must be smooth, and with an adjustable action so that they can be kept that way. Some resistance to movement is desirable, and this should be adjustable. Ideally this adjustment can be set on a cue by cue basis, so that slow cues can be operated against a greater resistance.

Finally a series of piano style keys could allow the various elements of a multi-part cue sequence to be triggered. Appropriately weighted or sprung keys could be velocity sensitive so that the harder the key is played the faster the cue runs. This would be ideal for the rapid cuing sequences often found in musicals.

The desk would automatically handle the loading of cues onto the desired playback, and cues could be switched from one playback to another at any time, even in mid cue.

The limitations of the state/cue model

Earlier I mentioned how important dynamics are in the live performing arts. So far the things I have suggested have been based on our existing ideas of how lighting should be structured. This is a model that is based on states - static stage lighting pictures. As lighting designers, we tend to focus on the creation of these states, and once they are decided upon we work out how we are going to get from one to another. Inexperienced lighting designers often have problems because they create a lighting state without giving enough thought to how they will get into it and out of it to the next state. This is hardly surprising, when the state/cue model enshrined in every lighting control positively discourages it. The emphasis then is on the static pictures, not the dynamics of change. Is there perhaps a lighting model that promotes the dynamics above the pictures?

The lighting score

One possible approach is to think of the lighting as a series of elements, such as the back light, a colour wash, the face light, and perhaps cyclorama colours. Each element would be plotted along a timeline, representing the duration of the performance - the lighting equivalent of a musical score. Obviously, a live performance by its very nature varies in its timing, so a series of cues would be given to the control desk at critical points during the stage action. Some of these would trigger lighting events just as cues do now, but others would simply be used to keep the lighting and the rest of the performance synchronised. The desk would speed up or slow down the flow along the timeline as required.

In this way, the point at which lighting changes finish, as well as when they start, could be controlled accurately. For example, the fifteen minute sunset would be adjusted as it runs to make it complete at exactly the dramatically correct moment, something that is hit-and-miss with our current theatre desks running a timed cross fade.

With moving lights included in the rig, the timeline approach could be applied to all the various parameters available, with different "staves" of the score showing, and allowing the manipulation of, intensity, colour, direction, etc. How much easier it would be to tell the control desk "here the intensity should increase, and there the colour should become warmer", rather than having to chop the lighting into static snapshots all the time.

Playability

I am not suggesting that the above ideas are the only way to go; they are just a few possible approaches to restoring to our lighting controls what the late Fred Bentham called "playability". And it is time for lighting to regain its place with the other live elements of theatrical performance, to join the actors, dancers and musicians in performing. It is time for lighting designers and operators to risk failure in order to chance success, as all performers do.