SUBJECTIVE APPRECIATION OF THE ARTIFICIAL LIGHT

OsvaldoDA POS – Francesca TRERE- Francesco BIONDIUniversity of Padua - Italy

Previous experiment.

How false informations and stereotypes can influence the observer's evaluation of a light source?

Material:- 4 (2 + 2) lamps- 4 presentations- 16 colour samples & atlas- 24 unipolar scales fot a semantic differential

Procedure:

20 observers had:

- to read the lamp specifications- to peform the colour match- to fulfill the semantic differential - to express their impressions

0 1 2 3 4 50

2

4

6

8

10

sc1

sc4

sc8

sc10

sc11

sc12

sc13

sc14

sc15

sc23

I1F2 I2F1

mean

evalu

ati

ons

Scales of the semantic differential

Artificial sources

freshsuperficial

slowsoft

maleclean

heavyclassic

coldclear

Results.

No significant difference in the semantic differential

for physically identical sources

Rather good colour constancy

Experiment 2.

Differences:

Personal interview with 12 university students in their private study room and in public study rooms.

Students' actual choices.

Shorter list of bipolar scales.

Changes in the technical sheets.

Results.

Preference for combined diffuse and concentrated illumination

General preference for warm ilght

Comparison between private and public places illuminations

Again non difference for evaluations of physically identical lights, witn one exception (*clear – confusing)

0.25 0.3 0.35 0.4 0.45 0.5 0.550.25

0.3

0.35

0.4

0.45

0.5

0.55

y

x

Chromaticity of the lights in the public study places

and in the private study rooms

In a CIE1939 diagram

0 1 2 3 4 5

1

2

3

4

5

6

7

8

9

10

SF

SH

DC

HL

CM

CW

CC

I1F2 I2F1

mean

evalu

ati

ons

SF slow fast

SH soft hard

DC dirty clean

HL heavy light

CM classic modern

CW cold warm

CC clear confusin

g

*

Artificial sources

Scales of the semantic differential

Conclusions.

Preference for diffuse + concentrated illumination

Preference for warm light

Selective preference for illuminations in public places

No influence of the manipulated informations on the students' evaluations