Related Experiment Video
Updated: Jun 8, 2026
05:10
Measuring the Behavioral Effects of Intraocular Scatter
Published on: February 18, 2021
Perceived glossiness and lightness under real-world illumination
Maria Olkkonen1, David H Brainard
1Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104, USA. mariaol@sas.upenn.edu
Journal of Vision
|October 2, 2010
Summary
Perception of object lightness is accurate under changing light, but glossiness perception is not. Geometric changes in illumination affect how we see surface shininess, not just brightness.
Area of Science:
- Visual perception
- Color science
- Computer graphics
Background:
- Perceptual attributes like color, lightness, and glossiness are crucial for object recognition.
- These perceptions must correlate with physical properties and remain stable despite varying illumination and viewing conditions.
Purpose of the Study:
- To investigate the perception of lightness and glossiness under geometric changes in illumination.
- To determine how observers adjust diffuse and specular reflectance for appearance matching under altered light fields.
Main Methods:
- Utilized a matching paradigm with computer-simulated spheres on a high-dynamic-range display.
- Observers adjusted diffuse and specular reflectance of a test sphere to match a reference sphere under different light fields.
Main Results:
- Diffuse component matches were veridical across geometric light field changes.
- Specular component matches were significantly affected by geometric light field changes.
- Independence principles confirmed: diffuse/specular matches were independent of each other and only slightly affected by roughness.
Conclusions:
- Lightness perception is robust to geometric illumination changes, unlike glossiness perception.
- Simple luminance histogram statistics do not predict appearance matches under geometric illumination shifts.
- The visual system's processing of diffuse and specular reflectance differs under geometric illumination variations.
Related Concept Videos
01:12Perceptual Constancy
Perceptual constancy is the ability to recognize that objects remain consistent and unchanged even when their appearance varies due to changes in sensory input. There are four main types of perceptual constancy: size constancy, shape constancy, color constancy, and brightness constancy.
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
Size constancy is the recognition that an object remains the same size, even when its image on the retina changes. For instance, a bus is perceived to be large enough to carry people, even if it looks tiny from...
01:18Imaging Biological Samples with Optical Microscopy
Optical microscopy uses optic principles to provide detailed images of samples. Antonie van Leeuwenhoek designed the first compound optical microscope in the 17th century to visualize blood cells, bacteria, and yeast cells. In 1830, Joseph Jackson Lister created an essentially modern light microscope. The 20th century saw the development of microscopes with enhanced magnification and resolution.
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
02:16Light Acquisition
In order to produce glucose, plants need to capture sufficient light energy. Many modern plants have evolved leaves specialized for light acquisition. Leaves can be only millimeters in width or tens of meters wide, depending on the environment. Due to competition for sunlight, evolution has driven the evolution of increasingly larger leaves and taller plants, to avoid shading by their neighbors with contaminant elaboration of root architecture and mechanisms to transport water and nutrients.
01:26Phase Contrast and Differential Interference Contrast Microscopy
Phase-Contrast Microscopes
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...
01:16Focusing of Light in the Eye
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...
01:05Total Internal Reflection Fluorescence Microscopy
Total internal reflection fluorescence microscopy or TIRF is an advanced microscopic technique used to visualize fluorophores in samples close to a solid surface with a higher refractive index, such as a glass coverslip. TIRF only allows fluorophores in proximity to the solid surface to be excited. When light from a medium with a lower refractive index (such as air) hits the glass coverslip at a critical angle, the light undergoes total internal reflection stead of passing through the glass.