Frédéric B. Leloup, Michael R. Pointer, Philip Dutré, and Peter Hanselaer, "Geometry of illumination, luminance contrast, and gloss perception," J. Opt. Soc. Am. A 27, 2046-2054 (2010)
The influence of both the geometry of illumination and luminance contrast on gloss perception has been examined using the method of paired comparison. Six achromatic glass samples having different lightness were illuminated by two light sources. Only one of these light sources was visible in reflection by the observer. By separate adjustment of the intensity of both light sources, the luminance of both the reflected image and the adjacent off-specular surroundings could be individually varied. It was found that visual gloss appraisal did not correlate with instrumentally measured specular gloss; however, psychometric contrast seemed to be a much better correlate. It has become clear that not only the sample surface characteristics determine gloss perception: the illumination geometry could be an even more important factor.
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Colorimetric and Specular Gloss Characterization of the Six Glass Samplesa
Sample Number
Sample Color
Gloss 20° (SGU)
Gloss 60° (SGU)
Gloss 85° (SGU)
1
White
82.7
1.19
2
Light gray
72.9
3
Light/Mid-gray
65.3
4
Mid-gray
46.1
5
Dark gray
22.8
6
Black
3.2
0.08
CIE values of samples obtained in SPEX mode and calculated under CIE illuminant D65 in combination with the CIE 1964 standard colorimetric observer. Average specular gloss values obtained in three basic geometries (20°, 60°, 85°), expressed in specular gloss units (SGU).
Table 2
Description of Each Test Condition, Together with the Measured Total Sample Illuminance (lux)a
Test Condition
Description
(lux)
(lux)
(lux)
A
Specular light source: high Background light source: off
250
—
250
B
Specular light source: medium Background light source: off
130
—
130
C
Specular light source: medium Background light source: low
130
250
380
D
Specular light source: low Background light source: high
15
1985
2000
The contribution originating from both the specular and the background light source, and , respectively, are indicated.
Image luminance and background luminance , gloss estimates , , and contrast gloss are presented for all six samples. Additionally, the calculated statistic , the average coefficient of consistency ζ, the coefficient of agreement u, and the variation of are listed.
Image luminance and background luminance , , and gloss estimates are presented for all six samples. Additionally, the calculated statistic , the average coefficient of consistency ζ, the coefficient of agreement u, and the variation of are listed.
Image luminance and background luminance , , and gloss estimates are presented for all six samples. Additionally, the calculated statistic , the average coefficient of consistency ζ, the coefficient of agreement u, and the variation of are listed.
Image luminance and background luminance , , and gloss estimates are presented for all six samples. Additionally, the calculated statistic , the average coefficient of consistency ζ, the coefficient of agreement u, and the variation of are listed.
Tables (6)
Table 1
Colorimetric and Specular Gloss Characterization of the Six Glass Samplesa
Sample Number
Sample Color
Gloss 20° (SGU)
Gloss 60° (SGU)
Gloss 85° (SGU)
1
White
82.7
1.19
2
Light gray
72.9
3
Light/Mid-gray
65.3
4
Mid-gray
46.1
5
Dark gray
22.8
6
Black
3.2
0.08
CIE values of samples obtained in SPEX mode and calculated under CIE illuminant D65 in combination with the CIE 1964 standard colorimetric observer. Average specular gloss values obtained in three basic geometries (20°, 60°, 85°), expressed in specular gloss units (SGU).
Table 2
Description of Each Test Condition, Together with the Measured Total Sample Illuminance (lux)a
Test Condition
Description
(lux)
(lux)
(lux)
A
Specular light source: high Background light source: off
250
—
250
B
Specular light source: medium Background light source: off
130
—
130
C
Specular light source: medium Background light source: low
130
250
380
D
Specular light source: low Background light source: high
15
1985
2000
The contribution originating from both the specular and the background light source, and , respectively, are indicated.
Image luminance and background luminance , gloss estimates , , and contrast gloss are presented for all six samples. Additionally, the calculated statistic , the average coefficient of consistency ζ, the coefficient of agreement u, and the variation of are listed.
Image luminance and background luminance , , and gloss estimates are presented for all six samples. Additionally, the calculated statistic , the average coefficient of consistency ζ, the coefficient of agreement u, and the variation of are listed.
Image luminance and background luminance , , and gloss estimates are presented for all six samples. Additionally, the calculated statistic , the average coefficient of consistency ζ, the coefficient of agreement u, and the variation of are listed.
Image luminance and background luminance , , and gloss estimates are presented for all six samples. Additionally, the calculated statistic , the average coefficient of consistency ζ, the coefficient of agreement u, and the variation of are listed.