Related Experiment Video
Updated: Jan 24, 2026

A Guide to Structured Illumination TIRF Microscopy at High Speed with Multiple Colors
Published on: May 30, 2016
Unique hue stimulus selection using Munsell color chips under different chroma levels and illumination conditions
Abstract:
To determine the role of chroma and illumination conditions on assessments of unique hue stimuli (UHs: Y, B, R, and G) 25 color normal observers selected Munsell color chips under controlled but different light sources that included simulated D65 daylight, incandescent (A), CWF and TL84, from two rotatable trays-one containing low and the other high chroma samples. Three independent evaluations were obtained from each observer with a gap of at least 24 h between assessments. A total of 2400 UH assessments were thus obtained. The mean, as well as the range and variability, in UH selections was calculated according to gender, illumination condition, and chroma. Results show statistically significant differences for uB and uR stimuli selections from the low to the high chroma sets under all lighting conditions, and for uY under light source A and CWF while differences in uG selections in different lighting conditions were statistically insignificant. No significant difference was found between male and female UH selections. Hue shift predictions based on CAT02 transform were found to agree well with observer responses under different illumination conditions. It was also found that observers' UH choices varied more for low chroma samples under different lighting conditions compared to high chroma samples. The highest variability was obtained under light source CWF, while the simulated D65 source resulted in the lowest variability in selections.
Related Concept Videos
Other Unique Bacteria
Second Uniqueness Theorem
In contrast, consider that the electric field is non-unique and apply Gauss's law in divergence form in the region between the conductors and the integral form to the surface...
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
What is Natural Selection?
Color Vision
Frequency-dependent Selection

