Color

COLOR

COLORKEY TOPICSVISIBLE SPECTRUM COLOR VISIONBLACK AND WHITECOLOR ADDITIONCOLOR SUBTRACTIONCOMPLIMENTARY COLORS

THE PhET SIMULATION CALLED COLOR VISION SHOWS HOW AN OBSERVER CAN PERCEIVE NEW COLORS BY ADDING WAVELENGTHS OF RED, BLUE AND GREEN LIGHT.

RedIncreasing DecreasingOrangeFrequencyWavelengthYellowGreenBlue IndigoVioletRemember Roy G. Biv

VISIBLE SPECTRUM

THE COLOR OF AN OBJECT THIS VIDEO SHOWS THAT THE COLOR AN OBJECT APPEARS DEPENDS NOT ONLY ON THE WAY THAT AN OBJECT REFLECTS COLORS, BUT ALSO ON THE COLOR OF THE LIGHT THAT IS ILLUMINATING THE OBJECT.

THE COLOR OF AN OBJECTTHE COLOR THAT AN OBJECT APPEARS DEPENDS ON THE SELECTIVE REFLECTION OF WAVELENGTHS OF THE OBJECT.THE WAVELENGTHS PRESENT IN THE LIGHT THAT IS ILLUMINATING THE OBJECTTHE COLOR RESPONSE OF THE OBSERVER

CLASSIFYING BY COLORTHE COLOR THAT AN OBSERVER ASSIGNS TO AN OBJECT IS THE COLOR THAT IT APPEARS UNDER WHITE LIGHT.

WHITE LIGHTLIGHT THAT IS MADE UP OF ALL VISIBLE WAVE LENGTHS OF EQUAL INTENSITY.SLIGHT VARIATION IN THE INTENSITY OF WAVELENGTHS CAN STILL PRODUCE THE SENSATION WHITE

WHITEAny combination of wavelengths that stimulates the red, blue and green sensitive cones equally will produce the sensation white.

BLACKTHE ABSENCE OF LIGHT

AN OBJECT WITH A CHARACTERISTIC COLOR MAY APPEAR BLACK IF IT APPEARS MUCH DARKER THAN ITS SURROUNDINGS.

THE COLOR BLACKTHE SENSATION THAT OCCURS AT NO OR LOW LIGHT INTENSITY.

AN OBJECT MAY APPEAR BLACK IF THE INTENSITY OF ITS REFLECTED LIGHT IS MUCH LOWER THAN THE SURROUNDINGS SO THAT IT APPEARS THAT NO LIGHT IS COMING FROM THE OBJECT.

COLOR ADDITIONTHE ILLUMINATION OF OBJECTS WITH MULTIPLE COLORED LIGHT SOURCES.

ADDITIVE PRIMARIESRED - BLUE GREEN THESE COLORS CAN BE USED TO STIMULATE THE THREE DIFFERENT CONES AND PRODUCE ALL POSSIBLE COLORS.

SIMULATION SURENDRANATHS CD HAS A SIMULATION OF COLOR ADDITION THAT ALLOWS YOU TO PRODUCE ANY COLOR BY VARYING THE AMOUNT OF RED, BLUE OR GREEN LIGHT PRESENT.

RULES OF COLOR ADDITIONTHE ADDITIVE PRIMARIES CAN BE USED TO PREDICT THE COLOR OF A WHITE OBJECTRED + BLUE = MAGENTABLUE + GREEN = CYANRED + GREEN = YELLOW RED + GREEN + BLUE = WHITE

APPLICATIONS OF COLOR ADDITIONSTAGE LIGHTINGCOLOR TELEVISION

COMPLIMENTARY COLORS TWO COLORS WHICH WHEN ADDED PRODUCE WHITE

RED + CYAN = WHITE BLUE + YELLOW = WHITE GREEN + MAGENTA = WHITE

COMPLIMENTARY COLORSSURENDRANATHS SIMULATION OF COLOR ADDITION CAN BE USED TO SHOW COMPLIMENTARY COLORS.

YOU MUST FIRST ADD TWO ADDITIVE PRIMARIES TO PRODUCE A SUBTRACTIVE PRIMARY.

WHEN YOU ADD THE THIRD ADDITIVE PRIMARY TO THIS SUBTRACTIVE PRIMARY, YOU WILL SEE THAT THEY ARE COMPLIMENTAY, BECAUSE THEY PRODUCE WHITE.

COLOR FILTERSThe PhET simulation called Color Vision shows that color filters are named by the color they pass.

COLOR SUBTRACTIONTHE PRODUCTION OF COLOR BY REMOVING WAVELENGTHS OF LIGHT.

SELECTIVE REFLECTION IS THE MOST COMMON PROCESS FOR COLOR SUBTRACTION.

SELECTIVE TRANSMISSION WITH COLOR FILTERS CAN BE USED ALSO.

SIMULATION SURENDRANATHS CD HAS A SIMULATION OF COLOR SUBTRACTION THAT ALLOWS YOU TO PRODUCE ANY COLOR BY VARYING THE AMOUNT OF YELLOW, CYAN AND MAGENTA LIGHT THAT IS PRESENT.

VIDEOA FLASHLIGHT CAN BE USED TO SHOW COLOR SUBTRACTION WHEN COLOR FILTERS ARE PLACED IN FRONT OF IT BEAM.

A WHITE PIECE OF PAPER MUST BE PLACED IN FRONT OF THE BEAM TO PRODUCE A REGION OF EQUAL BRIGHTNESS

SUBTRACTIVE PRIMARIESTHE SUBTRACTIVE PRIMARIES CAN BE USED TO REMOVE WAVELENGTHS FROM WHITE LIGHT TO PRODUCE ALL OTHER COLORS.

YELLOW CYAN MAGENTA

RULES OF COLOR SUBTRACTIONWHITE YELLOW = BLUE

WHITE CYAN = RED

WHITE MAGNETA = GREEN

COLOR SUBTRACTIONCommon applications:Mixing pigmentsTechnicolor movies

AFTER-IMAGETHE CONTINUED RESPONSE OF CONES AND RODS AFTER THE LIGHT STIMULUS IS REMOVED.

THE COLOR OF THE AFTER-IMAGE IS THE COMPLIMENT OF THE STIMULUS.

AFTER IMAGE

SUMMARYVISIBLE SPECTRUM ROYGBIVCOLOR VISIONCONES AND RODSBLACK AND WHITETHESE ARE RELATIVE TERMSCOLOR ADDITIONCOLOR TV, STAGE LIGHTINGCOLOR SUBTRACTIONMIXING PIGMENTS, MOVIES IN COLORCOMPLIMENTARY COLORSAFTER IMAGE