True color in chemistry is the color seen in a solution or compound in standardized conditions. It depends on electronic transitions in molecules, specifically absorption of a particular wavelength of light, and this depends on the structure of the compound.

To keep a neutral background, helping to reduce color distortion and bias.

Samples should be cleaned, dried, and scratched-free to obtain consistent haze measurements.

Keep light booths clean, maintain the light source lamps, readjust the calibrated light source, and ensure that dust and fingerprints do not settle on the viewing area.

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.

To keep the light box calibrated and to ensure accurate and steady lighting, clean the inside, replace the lamps when needed, check the calibration and record the hours use

The accuracy of colors is determined by comparing the values of the colors (L*a*b*) of a sample with a standard reference sample using tools such as spectrophotometers. The variation is measured as ΔE. The smaller the value of ΔE, the more accurate, the nearer to the target color.

A calorimeter is used to measure heat that is gained or lost during a chemical or physical reaction. A sample is taken in an insulated container, and a temperature change is measured. This assists in computing the alterations in energy by the equation Q = mcΔT, where Q is heat.

When detecting color differences, the first factors to consider when selecting a light source include its stability, directionality, lifespan, and the effectiveness of the ultimately obtained spectral curve. The illuminant of a colorimeter is a fixed bulb, such as a tungsten lamp，LED light or a long-life xenon lamp. However, for the same color sample, the results displayed by the instrument vary under different light sources. This is because different light sources cause different absorption and reflection of light on the sample, leading to differences in how both the human eye and the instrument perceive the color. 

In general, the D65 light source is used in the application of coil steel inks for construction. The D65 light source is equivalent to average daylight. Most coil steel inks for construction are used outdoors, and sunlight is regarded as the standard light source in outdoor environments. For household appliance coil steel inks, due to their usage characteristics, they are mostly used indoors. Therefore, the A standard light source is adopted for color measurement of samples based on indoor lighting conditions. The A light source is a carefully specified tungsten light source. Other light sources, such as fluorescent light sources, can be used in many types of applications. For example, some textile factories use fluorescent light sources. Therefore, a reasonable light source should be selected as the mutually recognized measurement method based on actual usage conditions and user requirements. Once agreed upon by both parties, color measurement must be conducted under the same conditions. This helps reduce unnecessary systematic errors and human errors, achieving the optimal consistency in color measurement. 

The 3nh high-precision spectrophotometric colorimeter adopts a combined LED light source with long lifespan and low power consumption, which includes UV (ultraviolet) and UV-excluded options. This design can meet the color difference detection needs of different users and supports the selection of multiple light source modes.

Ambient light may affect the test results and must therefore be kept to a low level for accurate haze meter results.