Emma Armstrong

The metamerism of 16th Century candle-light using modern technology

Experimental resultsApril 2008.

Objectives of practical session

• To gain a wide range of results with human perspective.

• To increase awareness of the project• As a progression update to the work carried

out so far.

Preliminary questionnaire

Before participants started the experiments, they were asked to fill in a short questionnaire detailing their age, gender, ethnicity, eyesight and technical ability. They then kept this and used it to fill in their answers for each station so that they were confidential and each participant would hopefully be able to answer freely. There were five stations in all.

Station One

Three sources of light – a 40w light-bulb, a tea-light and a battery-operated tea-light.

The main aim of the experiment was to gauge each person’s responses to each source.

This was to aid the section involved with recreating the atmosphere of a Jacobean theatre.

Station One

Hypothesis

I expect responses for the candle to be “warm”, “atmospheric” and “relaxing”. Responses for the light-bulb, I expect to be “harsh” and “bright”I think responses for the battery operated tea-light will be more varied as these are quite new on the market.

Because people have clipboards and are kept anonymous, I hope there will be a range of answers but feel they may be very similar.

Station One ResultsComments for each source were:Candle: Warm x7, relaxed x7, calm x5, peaceful x2, home, comfortable x3, drawn in x2, secure, spiritual, church,

stark, cold, isolated, uneasy, could go out at anytime, nice, eerie, secretive, time passage as light varies, soft focus, transported, ritual, intrigued, poetic, indoors, night-time, winter,

Lightbulb:Quite glaring but familiar and normal, blinded, clinical x2, filled with light, sharp, repelled, interrogated,

Harsh x4, irritable, bored, too bright x4, artificial, re-assured, nothing, inhospitable, distracting, archaic, clandestine (having a hidden aim), invaded, uncomfortable, softer focus, safe, anxious, confronted, backstage theatre, cosy, night-light, ready for bed,

Battery operated candle:Maybe in the right setting it would be better, not as bright as the candle x2, warm glow x2, much more

yellow, predictable pattern, static x2, no pool of light, too dull, merky like an ork, too consistent, different colour x2, peaceful, reliable, cosy, no fear of burning, darker x5, sinister, less warm, more orange x3, nice flicker, false, uninterested, less intense, flame less clear, cosmetic, more atmosphere the further away you stand x2, focus on the flame not light around it, less evasive, fake, relaxed but not as much as candle, weaker, plasticky,

Station Two

Setup: A tallow candle one foot away from a lux meter.

Simply a way of measuring the lux level of a tallow candle with a flax wick over a long period of time.

To allow the audience a deeper understanding in to the project and other experiments through an interactive method.

Station Two Results

Time

Stations Three and FourThese two stations were very similar. Station three was a white canvas

background with a candle shining on one half. On the other half was a 40w lightbulb, dimmed to 40% to match the lux level of the candle. Participants then put coloured gels in front of the lightbulb to see which one matched most closely.

Station four had the smae set-up but instead of a white canvas background, there were masks resembling skin colour. The idea of this was to again choose a gel to match. Both stations had 7 gels, all the same but labelled differently so no cheating was possible! Gels were: L103, L232, L443, L763, L205, L013 and L206.

Purpose: To see if it was possible to match the colour of a candle using existing and simple products.

To experiment with the use of light on a white canvas and a person’s face.

Stations Three and Four

Hypothesis

As time lapses, the gel choices will become less yellow and more orange shades.

30% of participants will choose the same gel in station three as in four.Participants will choose lighter colours on the masks than on the canvas.

Age and sex of participants will make no difference to the results but technical ability and eyesight will show trends.

Stations Three and Four

Only one person chose the same gel in station three as in station four. A 29 year old woman with perfect vision who classes herself as having no technical ability.

The following graphs show the choices of gels in relation to the answers on the questionnaire to spot any trends in age, gender etc.

443

103

205

206

232

013443

763

206

205

103

232

763

013

Participant Number

Overall choices of Gels. Stations three and four

443

103

205

206

232

013443

763

206

205

103

232

763

013

Participant Number

Male and female choices of Gels. Stations three and four

Male

Female

103

443

232

763

205

013

206

232

103

443

763

205

013

206

Age

Station 3

Station 4

To show age and gel choices in 3 and 4

Time (mins)

To show technical ability

443

103

443

232

763

205

013

206

232

103

443

763

205

013

206

Time in Minutes

Stations three and four

Conclusion and Evaluation

“Candles are multi-tonal whilst the gel is one tone”

Not as many trends as I had expected.

Wider range of results and gel choices on the mask station than on the canvas.

People found the mask station more difficult to decide on.

The light-bulb was set at 40% as this matched the candle when first lit. However, this would have been different as the candle burned down and the lux level dropped meaning that the lux levels of each source would have been different.

Station Five

Set-up: Candle on one side of a white canvas with a RGB parcan on the other side. Participants were asked to mix the red, green and blue until they thought they had a close match.

The parcan was a Eurolite RGB unit which was controlled by a Strand GSX lighting desk. This meant participants had 0-100 control units.

They were also asked to bring up each colour individually to see which colour they thought was brightest to see how the human eye perceives colour using red, green and blue

Station five

Hypothesis

The range of results will be small; each colour will be within 20% of each other.

As the time progresses, the amount of red will increase.

People will find it quite difficult to match, especially ones that are not used to lighting desks / technical equipment.

Results of station five

Out of 21 participants, 7 people thought blue was brightest, 10 people thought green, 2 people thought red and 2 people did not answer.

The two people who chose red were a 29 year old woman and a 64 year old man. The 29 year old was the same person who matched both gels in stations three and four.

Participant Red Green Blue

1 100 14 0

2 100 30 0

3 63 11 0

4 10 8 2

5 33 5 0

6 98 18 0

7 49 9 0

8 33 7 0

9 80 18 0

10 42 7 0

11 100 16 0

12 79 16 5

13 28 0 0

14 27 4 100

15 80 10 0

16 100 14 0

17 13 2 0

18 40 15 10

19 40 15 10

20 79 20 2

21 56 11 0

Overall results table

Results of Station Five – RGB LED colour mixing. General

Results of Station Five – RGB LED colour mixing. Age

28

1329

505121 22 37 22 22

32

64/63

29 4528

23/26 2229

22

Graph showing the times and results of participants

Male

Female

Graph to show male / female choices.

Choices in comparison with eyesight.

Colour Blind

Perfect eyesightUnsureLong Sighted

Unsure, wear glasses

Short Sighted

Not at all technically minded

Knows a little

Average technical ability

Knows quite a bit

Very technically minded

Station Five

Conclusion and Evaluation.

Not as many trends as I would have hoped although definite trends as participants added more red, they also added more green.

People found the task quite difficult but enjoyed it.

Shows that people perceive colours very differently.

Perhaps 0-100 is not enough units to be able to colour match sufficiently. Also, the parcan may be producing fewer bits than originally anticipated.

Future work

Gel 443 to be tested in Lancaster along with a range of other gels.

Test the colour temperature using a spectroradiometer and compare those results to the human tests.

To incorporate the flicker in to the electric chandelier

Look at multi-tones of candle flame and try to incorporate this.