Bezold–Brucke hue-shift as functions of luminance level, luminance ratio, interstimulus interval and adapting white for aperture and object colors

Abstract

four wavelengths are 'invariant' for a given L level or ratio. With higher L level, invariants shift as opposed pairs: to longer wavelength for b and y, shorter for g and r. With higher L ratio, b and y invariants shift some 10 nm longer but g and r remain about 508 nm and 493.5 c. With higher illuminant color temperature, invariants (1:10 cd/m2) shift shorter for b and y, r slightly longer (spectral to nonspectral 494 c) but g seems constant. Hue-shift data for real object color are very similar to aperture color. The full hue cycle is graphed to the recent extended wavelength scale for CIE dominant wavelength. Many effects are newly reported.

No difference in variability of unique hue selections and binary hue selections

“…Luminance differences are another possibility, but studies of the BezoldBrücke hue shift have produced mixed results. Some show a relatively large effect near the locus of unique green (510-550nm) compared to the loci of unique blue (475-480nm) and unique yellow (571-578 nm) [37][38][39][40][41], but others show comparable small shifts for the three colors [42][43][44].…”

Effect of purity on hue (Abney effect) in various conditions

“…It is also largely independent of the temporal mode of observation, since the curves for Parts A and B of Experiments 1-2 are very similar, unlike the Bezold-Brucke (B-B) effect which differs significantly between contrast and no-contrast modes. 11 Data for the contrast mode are probably the more significant, since the Abney effect is most commonly observed in simultaneous stimuli. It is worth noting that pilot experiments for three observers RP, IC, PB for Experiment 1A in adapting illuminants D65, D75, and D93 gave bimodal curves similar to the present results.…”

“…11 It is no better than using CIELUV or CIELAB hue angle but has the advantage of using the term "wavelength." Wavelength, but not hue angle, is well understood by other sciences and by the physiologists and neuroscientists in our color science community.…”

“…[3][4][5][6][7][8][9][10] The other principal effects on hue (other than wavelength itself) are luminance and illuminant color temperature. In real life outside the laboratory, the purity effect is related to the luminance (or Bezold-Brucke) 11 effect on hue since a three-dimensional object has highlight and shadow giving varying chroma and lightness. Both effects comprise hue shifts, and improve visual perception of three-dimensional objects by adding hue differences to the more obvious lightness differences.…”

“…Hence one might expect that the Abney and Bezold-Brucke effects would have similar influences on hue shift, as previously suggested. 11 The luminance effect is better agreed in the literature than the purity effect, on which the various data sets [1][2][3][4][5][6][7][8][9][10] over 100 years' research lack agreement and urgently need resolution.…”