In the study of chemical reactions, calorimetry deals with changes in heat (energy and enthalpy). Spectrophotometry is the measurement of the light absorbance or light transmittance to determine the concentration or color of a solution. The first one monitors the thermal processes, whereas the second one addresses the aspects of light and color.

The haze meter test assesses the degree of light scattering that occurs when light traverses a transparent or translucent material, producing a percentage that quantifies example or cloudiness.

The repeatability is an important parameter for the accuracy of the colorimeter. Threenh Technology portable colorimeter for color measurements tandard deviation ΔE*ab is within 0.03 (Measurement condition: the average value of 30 measurements on the white board at an interval of 3s after calibration). Each colorimeter can pass the qualified inspection before leaving the factory to ensure it conforms to the standard of China Metrology Institute.

To take care of a haze meter to make it last longer, ensure that it is cleaned, recalibrated regularly, and stored in a dry, dust-free place. 

The ΔE (Delta E) formula of the CIELAB color space is usually used to measure color difference. The difference is measured in a colorimeter or spectrophotometer to gauge the level of perceptibility of the difference between two samples in terms of L*a*b*.

Color is a qualitative and quantitative measure. Qualitatively, it can be characterized by the hue, the saturation, and the brightness. It is quantified in terms of color spaces, such as L*a*b* or RGB, in terms of numerical values based on devices such as colorimeters or spectrophotometers.

They provide accurate and repeatable assessments of color in various settings for the purpose of avoiding inconsistencies in mismatched items and ensuring steady production or branding.

The most common standard measuring gloss is ASTM D523, which covers the procedures of using a gloss meter at 20°, 60°, and 85° angles. The other international standard that is widely used in industrial and laboratory applications is the ISO 2813.

The measurement of color varies according to context in several units. Such common units are L*a*b* (CIELAB), RGB (Red-Green-Blue), and color difference (Delta E). In light absorption, there are no units assigned to absorbance. But the quantitative analysis of absorbance obeys Beer's Law in colorimetry.

Colors look different under various lights mainly because of metamerism—a phenomenon where two colors that match under one light source fail to match under another, caused by differences in the spectral composition of light.

Different lighting varies the color perception of objects. Warm light, like that from incandescent bulbs, tends to make colors more yellow, while daylight presents a bluish tint. Our color vision system plays a compensating role using a mechanism called color constancy.

Every light source emits light with a unique "spectral fingerprint" (i.e., the range and intensity of wavelengths it contains). This directly affects how an object’s surface reflects light and how our eyes perceive its color.