Lighting up Shakespeare with LEDs

June 26, 2009
A student project has analyzed the theatrical lighting used for William Shakespeare’s plays, and has reproduced them using LED fixtures.
Cresset Lighting up Shakespeare It combines Jacobean history (the period when Shakespeare’s plays were written and first performed) with the latest LED technology to authentically and safely create a unique audience experience. The project provides two aspects to the Jacobean stage – covering the stage with light as if lit by chandeliers and using prop lighting such as cressets and lanterns.

The placement of the stage fixtures and prop lighting has been implemented by thorough research. The stage lighting represents the chandeliers that would have been hung above front-of-stage and the audience. The actors would have been lit from the chandeliers at the front, the footlights and also chandeliers above the stage. The cressets would have been used to welcome the audience at the doors, and then moved to the side of the stage when the play started. The lanterns would have shown the time of day within the play and also add a little extra light to actors’ faces. Because of the nature of the project, both indoor and outdoor lighting techniques were used.

Both stage lighting and prop lighting have two elements; the colour and the flicker. Shakespeare’s stage would have been lit using tallow candles, which were made from animal fat and burnt used a wick made from rush or flax. For the purpose of the project, these candles were sourced from a company who specifically make them in the same way they would have been made in the Jacobean era. This was an important decision; if the lighting is to recreate the candlelight then it must be as accurate as possible.

Replica Jacobean lantern Using the candles, a variety of experiments were conducted. The first was to see if humans could match a variety of colours of LEDs to the tallow candle. A viewing box was constructed so on one side, participants saw the reflection of a candle and on the other they saw the reflection of LEDs. The task was to alter the brightness of each LED – in one experiment they had orange and white and in another, they had orange, green and white. This was a very interesting experiment; although no two participants gave the same results, there was a clear trend that as participants added more orange, they also added more green and white. This was then worked out in percentages which brought the results closer together although still not perfectly matched. Participants found it easier to match the colour using the white and yellow LEDs but were happier with their results using the orange, white and green – it just took longer to achieve the results they were pleased with.

The choice of colours came from another experiment involving a spectroradiometer and a darkened room. The tallow candle was measured for its spectrum data and chromaticity values on a SpectraScan PR-650 (Photo Research Inc.) under a 2-degree standard observer setting. The chromaticity values of the tallow candle are x= 0.534, y=0.412. By plotting this on the CIE XYZ colour space and together with the values for the chosen LEDs (white and yellow) it could be predicted if the LEDs were going to be feasible.

The candle was on the line segment of the white and yellow LEDs meaning that, in theory, the colour of the tallow candle could be matched using these two LEDs. The gamut for the orange, white and green LEDs gave an excellent range of colours so that if the candle were to burn down and become more orange, this could be accounted for. If this had happened using the white and yellow, it would not be possible to match the LEDs to the candle. After testing the various LED combinations on the spectroradiometer, the orange, white and green (OWG) option was much easier to match and, in fact, an exact match was achieved.

Lighting the stage

Pulsar Chromaflood 200 The OWG option has been used for the prop lighting. Originally, the project aimed to gain a true metamer (i.e. to match the spectrum of the candle exactly) but this has not been completely possible. The LEDs are a perfect match when a white tile is positioned so as to reflect the light, but using different coloured backgrounds does not always create the same chromaticity values. The LEDs are mono-chromatic, whilst the candle emits the full spectrum; to overcome this problem, a huge range of LEDs would need to be used. With blue, green and yellow backgrounds the LEDs perform very well. However, with red and orange, the LEDs struggle.

The stage lighting is provided by Chromaflood 200 fixtures from Pulsar, containing a mixture of RGB LEDs. Again, these were tested on the spectroradiometer and compared to the tallow candle. Originally, a 6-bit DMX control programme was used, but this did not provide the fine-tuned mixing that was required to achieve the correct colour. Instead, an 8 bit (0-255) programme was used and this was able to give the required results. As with the OWG, the RGB had some problems when using different coloured backgrounds and unusually, it had most of the issues with the same colours as with OWG.

The Pulsar fixtures blend the colours extremely well even from only a few feet away, which has proved invaluable for testing procedures. The 8-bit control is a must for fine tuning as even 1 unit of an extra colour will change the chromaticity value by a noticeable amount. These fixtures are controlled using a generic lighting console with a random chase function to add a “flicker”. The flicker can be altered depending on the mood of the play and also the action taking place. Each sequence has a variety of step changes in intensity and in time for that particular intensity to stay on. The more the actors are moving about (for example during a fight scene) the more the “candles” can “flicker”.

The control for the cressets and lanterns is completely custom-made and achieved through an 8-pin PIC and some simple programming. The programme uses pulse-width modulation (PWM) control to set the LED values and also adds a random flicker so there is not a noticeable pattern. The lanterns contain a candle with a silicone “flame” inside an adapted off-the-shelf outdoor candle holder. The cressets contain a fan and a moving “flame” encased in a specially made wrought-iron casing. They both run off AA batteries, with the cressets lasting about 3 hours. Using rechargeable batteries (3200mAh or more) makes this a very easy and safe option whilst reducing the cost.

The lighting of Shakespeare’s stage has been widely researched by academics but due to the nature of candles and the history of using them in theatres, health and safety advisers are reluctant to allow them to be used. This project takes the facts and turns them in to something useable allowing off-the-shelf items to be used, as well as custom-made ones for the more electronically minded.

This research will be put in to practice in July 2009 during a week of Shakespeare’s shows at Liverpool Hope University’s beautiful outdoor space – see for tickets and information.