Subtractive Colour Theory Flashcards

Specular Reflection

Reflection from smooth surfaces, such as mirrors, where parallel light rays remain parallel after reflection, creating a clear image.

Diffuse Reflection

Reflection from rough surfaces, like paper, where parallel light rays scatter in many directions after reflection, resulting in no clear image.

Why do we see objects?

We see objects because of reflection. Light reflects off objects, and the intensity and color of the reflected light determine our perception of the object's appearance.

What happens when white light interacts with a green plant?

The plant absorbs Red and Blue light while reflecting Green light due to pigments like chlorophyll. This selective reflection makes the plant appear green to our eyes.

How are different colours made?

Different colors are perceived through reflection, starting from white light (Red+Blue+Green). Selective absorption and reflection of different wavelengths result in the perception of various colors.

Role of cones in human sight

Eye cells (cones) are stimulated by light reflected off objects. The brain interprets these signals as color. Different cones are sensitive to red, green, and blue light, allowing us to perceive a wide range of colors.

Magenta filter

A magenta filter subtracts green light from white light, transmitting red and blue light. Thus, objects viewed through a magenta filter appear with varying shades of red and blue.

Yellow filter

A yellow filter subtracts blue light from white light, transmitting red and green light. Objects viewed through a yellow filter appear with varying shades of red and green.

Cyan filter

A cyan filter subtracts red light from white light, transmitting green and blue light. Objects viewed through a cyan filter appear with varying shades of green and blue.

Additive Colour Theory

Additive color theory explains how lights of different colors combine to form other colors when shining on a white surface. The primary colors are red, green, and blue, which combine to create white light.

Absorption

Absorption occurs when light energy is taken into the molecules of a surface, converting the light energy into other forms of energy, such as heat.

Reflection

Reflection is when light bounces off a surface. The angle of incidence is equal to the angle of reflection for smooth surfaces.

Transmission

Transmission is when light passes through a surface. Transparent materials allow most light to pass through, while translucent materials allow some light to pass through but scatter it.

Emission

Emission is when light is produced by the material itself, such as the light from a light bulb or the glow of a firefly.

Subtractive Theory

Subtractive color theory explains how colors are absorbed or partially reflected when light interacts with a material. This is used in mixing paints and creating colors by subtracting certain wavelengths of light.

Black

Black is the perception when all colors of light are absorbed by an object, and no light is reflected to the eye.

White

White is the perception when all colors of light are reflected by an object, and all wavelengths of light reach the eye.

Subtractive Primary Colors

The subtractive primary colors are cyan, magenta, and yellow. These colors are used in printing and painting because they can be combined to create a wide range of other colors by subtracting different wavelengths of light.

Filters

Filters are transparent objects that subtract colors from white light by absorbing certain wavelengths and transmitting others. They are used to change the color and intensity of light.

Magenta filter

A magenta filter subtracts green light, allowing red and blue light to be transmitted. This results in objects appearing magenta or purple when viewed through the filter.

Yellow filter

A yellow filter subtracts blue light, allowing red and green light to be transmitted. This results in objects appearing yellow, red, or green when viewed through the filter.

Cyan filter

A cyan filter subtracts red light, allowing green and blue light to be transmitted. This results in objects appearing cyan, green, or blue when viewed through the filter.

Light

Light is energy waves in the visible part of the electromagnetic spectrum that can be detected by the human eye, enabling us to see and perceive the world around us.