One of the most common methods for measuring color quantitatively is spectrophotometry. A
spectrophotometer measures the amount of light reflected or transmitted by a sample at different wavelengths. After the data is collected, software analyzes it and creates a "spectral curve". This curve shows the amount of light reflected at every wavelength and is unique to each color.A colorimeter is an instrument that can also be used to measure color quantitatively. While a
spectrophotometer measures the amount of light absorbed or transmitted by a sample at different wavelengths, a colorimeter measures the light intensity of a specific wavelength absorbed or transmitted by a sample.