Search results
Results From The WOW.Com Content Network
Contrast is the difference in luminance or color that makes an object (or its representation in an image or display) visible against a background of different luminance or color. [1] The human visual system is more sensitive to contrast than to absolute luminance; thus, we can perceive the world similarly despite significant changes in ...
The eye has different responses as a function of wavelength when it is adapted to light conditions (photopic vision) and dark conditions (scotopic vision). Photometry is typically based on the eye's photopic response, and so photometric measurements may not accurately indicate the perceived brightness of sources in dim lighting conditions where ...
The human eye can function from very dark to very bright levels of light; its sensing capabilities reach across nine orders of magnitude. This means that the brightest and the darkest light signal that the eye can sense are a factor of roughly 1,000,000,000 apart. However, in any given moment of time, the eye can only sense a contrast ratio of ...
The human eye can only see light in the visible spectrum and has different sensitivities to light of different wavelengths within the spectrum. When adapted for bright conditions (photopic vision), the eye is most sensitive to yellow-green light at 555 nm. Light with the same radiant intensity at
There are two luminous efficiency functions in common use. For everyday light levels, the photopic luminosity function best approximates the response of the human eye. For low light levels, the response of the human eye changes, and the scotopic curve applies. The photopic curve is the CIE standard curve used in the CIE 1931 color space.
Reduction of brightness of the rest of the scene by constriction of the pupils; Reduction in contrast of the rest of the scene by scattering of the bright light within the eye. Reduction in contrast by scattering light in particles in the air, as when the headlights of a car illuminate the fog close to the vehicle, impeding vision at larger ...
For instance, the luminance of a 30 mm 2 pupil was found to be only twice that of a 10 mm 2 pupil. In other words, to match the apparent brightness of light entering a 30 mm 2 pupil, the luminance of light entering through a 10 mm 2 pupil had to be increased by a factor of two, instead of the expected factor of three. [1]
The Chubb illusion is similar to another visual illusion, the contrast effect.The contrast effect is an illusion in which the perceived brightness or luminance of an identical central visual target form on a larger uniform background varies to the test subject depending on the ratio of the central form's luminance to that of its background. [4]