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Born D G - - 1969
Four pigeons were trained to respond on one of two keys in the presence of one color-form display, and on the other key when a second color-form display was present. Both responses were maintained on a 2-min variable-internal schedule of reinforcement. Subsequently, stimulus control acquired by components of the compound ...
Rhodes E C - - 1969
The supplementary light method of Reule was applied to calibrate a simple phototube photometer to an absolute accuracy of +/-0.006% (95% confidence limits). The photometer was then used to determine the photometric accuracy of a General Electric recording spectrophotometer. The photometric scale of this instrument was shown to be accurate ...
Nichols L W - - 1968
An ir line scan instrument has been developed that scans a scene simultaneously with three separate spectral regions and produces an image of the scene as a color photograph. The three spectral regions are 0.5-1.0 micro, 3.0-5.5 micro and 8.0-14.0 micro. The ir detectors used are Si, InSb, and Ge:Hg, ...
Werner A J - - 1968
The CIE and CIE-UCS color systems are reviewed as background for discussing uniform, color space. Computed luminosities and trichromatic coordinates for various thicknesses of several Corning filter glasses are presented. These data are used to illustrate graphically several tridimensional color spaces, including Wyszecki's proposal for a uniform space using the ...
Meier R H - - 1968
An apparatus is described which permits the visual display and controlled visual match between a standard color and a color which is the result of mixing a pair of homogeneous spectral colors in a precisely measurable luminance ratio. The luminance of the binary mixture either remains constant or changes proportionately ...
Perry B L - - 1967
Multistage color photography without the usual attendant loss of color integrity is described. The technique was evolved for fabricating a four-color, patterned transparency requiring a high degree of pattern precision and close control of color characteristics. The necessary accuracy is achieved through an enlargement-reduction multistage photographic process. Color integrity is ...
Daw N W - - 1967
The majority of ganglion cells in the retina of goldfish have receptive fields organized so that the cells respond particularly to simultaneous contrasts of color. The receptive fields are concentrically arranged. If the cell is excited by red light in the center, then it will also be excited by green ...
Judd D B - - 1967
Published work in physiological optics at the National Bureau of Standards is summarized under the headings: evaluation of light-dark patterns, light measurements, color measurement, color differences, and color perception. The bearing of this work on standard methods of the American Society of Testing and Materials, of the Illuminating Engineering Society, ...
D'Amato M R - - 1966
Explicit cue-producing responses were employed to study attending behavior in the monkey. The subjects learned a discrimination based on compound stimuli, a vertical bar embedded on a red ground versus a horizontal bar on a green ground. On some trials only one of the two stimulus components was presented (red ...
Krauskopf J - - 1965
A method for determining the spectral sensitivity of the different color mechanisms of the human eye uses the pattern of color names applied to small, brief, dim, monochromatic flashes. Such responses are often due to the activation of single neural units. Preliminary spectral sensitivity curves for two color mechanisms have ...
Crescitelli F - - 1965
Antelope ground squirrels (Citellus leucurus) were able, after conditioning, to respond correctly to a port illuminated with light at a wavelength of 460 nanometers. This color randomly presented at one of two positions, was correctly selected in reference to a second port illuminated with light at 500, 520, 569, and ...
McCollough C - - 1965
An aftereffect of color which depends on the orientation of lines in the test field may be obtained by presenting a horizontal grating of one color alternately with a vertical grating of a different color. Like the aftereffect of adaptation to chromatic fringes produced by prismatic spectacles, this aftereffect is ...
THOMPSON T - - 1965
Male Siamese Fighting Fish (Betta splendens) were conditioned to emit an operant response sequence reinforced by presentation of a model of a male Siamese Fighting Fish in aggressive display. Operant response rate varied as a function of the color of the model with respect to the color of the subject.
BOYNTON R M - - 1964
A method of hue measurement, in which an absolute color-naming procedure is utilized, has been applied to spectral stimuli delivered as flashes at 0 degrees, 20 degrees, and 40 degrees eccentricity in an otherwise dark field. The method yields very reliable measures, especially at 0 degrees. Color-naming at 0 degrees ...
Sousa J A - - 1964
Exposure to light of o-nitrobenzylpyridines at -185 degrees C yields a long-lived colorless intermediate which is converted to a colored isomer on warming.
Bivens L W - - 1961
A very close relationship has been found between hue discrimination thresholds and the differences in wavelength necessary to produce "full color" from two monochromatic light sources. This finding suggests a need for certain research in the area of color induction.
Hurst V J - - 1961
All flints containing unstable impurities are susceptible to patination. The rate of patination varies with many factors: (i) the texture and microstructure of the flint; (ii) its permeability; (iii) the kind, proportion and distribution of impurities; and (iv) environmental factors, such as temperature and soil chemistry. The thickness of the ...
CLARK G L - - 1959
The effect of x-rays at various voltages and intensities, with monochromatic and polychromatic beams, on Ektachrome daylight and artificial-light film was investigated. The colors were rated according to the Munsell color system and ranged over all the spectrum except red. The color in terms of hue, value, saturation, and chroma ...
Hartridge H - - 1948
Until a few years ago it was possible to account for nearly all the aspects of human color perception on the basis of the three-color theory, but such is no longer the case. This is largely due to improvements in the older methods of investigation and to the invention of ...
Chapanis A - - 1947
Determinations of minimum light thresholds as a function of time in the dark have been made for four color normal, three deuteranopic (or deuteranomalous), and four protanopic (or protanomalous) subjects. Measurements were made with red, reddish orange, yellow, green, violet, and white test lights. Dark adaptation curves for the deuteranopes ...
Ezell B D - - 1946
The fleshy roots of the sweet potato are shown to contain appreciable amounts of yellow pigments other than beta-carotene. The carotene/total-pigment ratio varies among different varieties and within varieties. In the varieties tested, the carotene/total-pigment ratio increased with increase in intensity of yellow color. Triumph, a very light-colored variety, contained ...
Chase A M - - 1938
The absorption spectra of visual purple solutions extracted by various means were measured with a sensitive photoelectric spectrophotometer and compared with the classical visual purple absorption spectrum. Hardening the retinas in alum before extraction yielded visual purple solutions of much higher light transmission in the blue and violet, probably because ...
Hecht S - - 1936
1. Protanopes and deuteranopes show one maximum of wavelength discrimination which occurs near their neutral point in the region of 500 mmicro (blue-green for color-normal). The value of the just discriminable wavelength interval Deltalambda is about 1 mmicro at this point and is much like the normal. To either side ...
Hecht S - - 1936
1. Wavelength discrimination for the colorblind is entirely determined by saturation differences in the spectrum. From the neutral point to the short-wave end, his spectrum may be completely matched by 440 mmicro plus white; to the long-wave end by 650 plus white. The proportion of color to white, hence the ...
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