**7.1 Color measurement is divided into three categories**


### **8. Color matching**


that can also be used to assess sample color consistency. The spectrum reflectance of the varnished layer is measured using spectral imaging, which is a physical quantity that is independent of the measurement apparatus. An ordered collection of the spectral reflectance of its pixels can be stored as a digital image based on this physical quantity. Spectral pictures have a number of benefits, including the following:


**Colorimetry by spectrophotometer:** The photoelectric method's main premise involves converting the glowing energy conveyed by a stained system to rechargeable energy, which can be detected more easily, using a photoelectric detector. A light source with a constant intensity is required by the instrument.
