The main instruments used to detect color are spectrophotometers and colorimeters (including photoelectric integrating colorimeters). 

Spectrophotometer: High-precision option. It analyzes the full visible light spectrum to measure color accurately. Suitable for complex scenarios like textured surfaces, special effect colors, or batch consistency checks in industries such as paint and coatings. 

Colorimeter (Photoelectric Integrating Colorimeter): Cost-effective and portable. It uses RGB filters to measure tristimulus values directly. Ideal for quick color difference detection in simple applications. Key Selection Tip Choose based on accuracy needs: use a spectrophotometer for high-precision color measurement, and a colorimeter for fast, basic color difference checks.

The machine used to measure color is primarily called a colorimeter or spectrophotometer. 

Spectrophotometer: The most common and precise type. It analyzes light reflected/transmitted by an object across the visible spectrum to quantify color accurately. A spectrophotometer can measure colors on smooth or matte surfaces, as well as textured, glossy, mirror-like surfaces, and special effect colors. It measures the reflected light of a sample at a fixed angle (e.g., 45˚) or captures light reflected at all angles to calculate color measurements that closely match what the human eye perceives. Additionally, similar to how humans flip a sample to view colors from different angles, a spectrophotometer is suitable for measuring a variety of materials and surface characteristics. Widely used in industries like paint, textiles, plastics, Chemicals, Pharmaceuticals, and printing. 

Colorimeter: Also called photoelectric integrating colorimeter, a simpler, more cost-effective option. It measures color based on three primary colors (RGB) and is suitable for basic color matching needs. A photoelectric integrating colorimeter is a color measurement device based on the photoelectric integration principle. It directly measures the tristimulus values XYZ of an object's color using three color filters (red, green, blue) and silicon photocells as three sensors. The color measurement principle of this instrument imitates the human eye's mechanism of perceiving the three primary colors (red, green, blue). It corrects the relative spectral sensitivity of the detector through color filters to match the CIE-recommended spectral tristimulus value functions x(λ), y(λ), and z(λ).

Spectrocolorimeter: Combines the functions of spectrophotometers and colorimeters, offering both spectral data and color space values for comprehensive analysis.

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.

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.

Colorimetry is a method that applies color intensity to ascertain the chemical concentrations. It is founded on Beer-Lambert Law, whereby the absorbance at a given wavelength is proportional to the concentration. It is popular in environmental and biochemical testing.

A spectrophotometer and colorimeter are certain instruments used by scientists to measure color by quantifying reflected or transmitted light. The results are presented in color spaces, such as L*a*b*, RGB, or XYZ. This enables the accuracy of comparison and tracking of the changes in color in chemical or material research.

Colorimeters or spectrophotometers are used to measure liquid color. They measure light coming through or reflecting off the liquid. Readings can be reported as Lab*, RGB, or absorbance units. So that objective color analysis can be used to control quality, or to measure chemical concentration.

A colorimeter or spectrophotometer should be used to measure the color of a solution. The instrument directs light through the liquid and quantifies absorbance at certain wavelengths. The values obtained indicate the color intensity of the solution and, by default, the concentration of the solution.

The color of chemical products is measured by using a colorimeter or spectrophotometer. The instruments measure the amount of light that gets absorbed or reflected by a substance. It may be used to determine concentration, purity, or compliance with product standards.

Gloss levels are usually of five types, namely, matte, eggshell, satin, semi-gloss, and high gloss. These categories are of rising levels of reflectivity of the surface and are utilized to characterize the completion of paints, coatings, and other substances.

Gloss level is not given out in percentage but in gloss units (GU). In practice, however, 100 GU is considered 100 percent reflective. To contrast visually, the 20-40 GU is a low-gloss surface, and 85 or more is almost 100 percent mirror-like reflection.

An 80 gloss surface will reflect less light as compared to a 100 gloss surface. Both are said to be high gloss, although 100 GU (or higher) reflects almost as much as a mirror. The distinction can be slight in graphic terms, but major in specific uses.

The gloss meter is used to measure the gloss level: it is a device that directs the light at a fixed angle and reads the intensity of the reflected light. The angles, such as 60°, 20°, or 85°, are applied depending on the type of surface and the range of gloss.

Powder paint gloss levels are classified as:

● Flat: 0–10 GU

● Satin: 11–40 GU

● Semi-gloss: 41–70 GU

● Gloss: 71–85 GU

● High Gloss: 86+ GU
 

These are measured at a 60° angle for standardization.

Gloss is the general reflectivity of a surface, which encompasses a variety of degrees. One particular type of finish is high gloss, which has the maximum shine and reflectance. It increases the richness but emphasizes flaws as compared to satin or matte.

The gloss meter is used to measure gloss at typical angles (typically 20°, 60°, or 85°). The instrument illuminates the material and measures the amount of light reflected and states the outcome in gloss units (GU), which is related to perceived brilliance.

Powder paint gloss levels are commonly classified as:

● Flat/Matte: 0–10 GU

● Satin: 10–40 GU

● Semi-Gloss: 40–70 GU

● Gloss: 70–85 GU

High Gloss: 85+ GU
These ranges can vary by manufacturer and application angle.

Gloss is a broad term to describe the reflectivity of a surface. Whereas high gloss is a specific term that has the highest reflectance (usually more than 70 GU). High gloss finishes are shiny, mirror-like, and exhibit more surface blemishes than lower gloss finishes.

The LAB color space defines colors in a three-dimensional model: Lightness (L), red–green axis (a), and blue–yellow axis (b). It's a globally recognized standard supported by most modern color measuring devices. CIELAB is a standardized, device-independent system designed to map all visible colors that the human eye can perceive.

The LAB color space uses three values to define any color, each representing a specific dimension:

L (Lightness): Ranges from 0 to 100. It measures the brightness of the color, where 0 is pure black and 100 is pure white.
A (Red-Green Axis): Ranges from approximately -128 to +127. Positive values represent red tones, while negative values represent green tones.
B (Yellow-Blue Axis): Ranges from approximately -128 to +127. Positive values represent yellow tones, while negative values represent blue tones.

A colorimeter is sufficient when measuring similar materials or batches with stable conditions. Suitable for fast, low-cost color checks where high precision is not required. Quick quality control in plastics, paint batch consistency, food color grading (e.g., fruit ripeness), and basic printing checks.

A spectrophotometer is recommended when you need professional, maximum color accuracy or when testing materials with variable surfaces – such as glossy or textured samples. Like textile dye formulation, cosmetic shade matching, medical device color calibration, high-end printing (e.g., packaging for luxury goods), and material spectral research. learn more Understanding Spectrophotometric Parameter Measurement

A spectrophotometer measures the full visible color spectrum (typically 400–700 nm). It offers significantly higher precision and enables detailed evaluations – including spectral curves, ΔE values, and color distance measurements. It is the preferred choice for demanding applications in labs or color development environments. learn more..

The core difference between a colorimeter and a spectrophotometer lies in their light measurement methods. A colorimeter measures color values based on the tristimulus method (e.g. LAB or RGB) and compares the sample to a reference. It's ideal for quick, repeatable measurements under consistent conditions – such as in production or incoming goods control.

A Spectrophotometer color measuring device objectively determines the color of a surface. It is used wherever accurate color matching, reproducibility or deviation control is needed – for example in quality assurance, product development or incoming goods inspection.

Spectrophotometer color measuring devices primarily perform three key tasks:

Capture color information: They detect light reflected, transmitted, or emitted by a sample using optical sensors.
Quantify color data: They convert the captured optical signals into standardized numerical values, such as RGB, CMYK, or CIELAB coordinates.
Compare color consistency: They compare the measured color data of a sample against a target or standard to assess color accuracy and uniformity.

Record the L*a*b values of the sample and the reference with a calibrated spectrophotometer or colorimeter. Compute the difference in the color by use of ΔE. The lower the Delta E, the more accurate the result. The difference in energy, ΔE < 1, is generally assumed to be invisible to the eye.

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.

To quantify color change, take the original L*a*b* values of a sample, and reread after exposure or processing. Compute the difference as 1/2(Emut1 Emut2). The larger the value of ΔE, the more obvious the change of color is, which can be used in quality or stability testing.

The most important equation is A = 2εcl, where A is the absorbance, 2 is a constant, ε is the molar absorptivity (L/mol cm), c is the concentration (molL-11), and l is the path length (cm). This can be used to relate the absorbance to the concentration, allowing quantification through colorimetric assays.

The principle of colorimetry is the law of Beer-Lambert, which says that the intensity of light absorbed by a colored solution is proportional to the concentration of the absorbing species and the path length. It measures the extent of light that is absorbed at certain wavelengths.

The color measurement theory is the quantification of the interaction of materials with light, either absorption, transmission, or reflection. It employs standard colour spaces (such as CIELAB) and devices (colorimeters, spectrophotometers) to code the visual colour into objective and reproducible data.

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.

CIELAB L*a*b* values are the most standardized units in the use of color measurement. These determine values of lightness (L*), red-green (a*), and blue-yellow (b*). The color differences between the two samples can be measured through ΔE.

The color may be quantified in L*a*b* (CIELAB units), RGB values, CMYK (printing), and ΔE (color difference). Colorimetric assessment measures also apply spectral reflectance and absorbance (A), particularly in liquids and solutions.

Color measurement methods involve visual approximation (against color charts), colorimetry (by means of filters and detectors), spectrophotometry (a more detailed spectral analysis), and image analysis by computer. These are color measurement methods that are applied in the laboratory, production, and quality assessment.

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.

Techniques of measuring color are visual color comparison, colorimetry (with colorimeters) and spectrophotometry (measuring spectral reflectance), and image analysis. Both techniques measure the reflection or absorption of light by materials and are commonly quantified. Therefore standardized in color spaces such as CIELAB or RGB.

Yes. Ultrasonic coating thickness gauges can pinpoint layers within a multi-coat system. Users can examine the separate thicknesses of a primer, base coat, and clear coat. In contrast, magnetic and eddy current gauges usually measure the overall thickness of the coating. 

There are many factors that can influence accuracy such as surface roughness, temperature, substrate material, and calibration settings. For ferrous metals, external magnetic fields can also distort measurements. Proper calibration and preparation will help reduce the impact of these factors.

Compared to an analog model, digital gauges not only provide more accuracy, but also allow for greater repeatability and are easier to work with. Advanced digital gauges allow for features such as data storage and automatic calibration and statistical analysis. For these reasons, digital gauges are the preferred choice for professional applications.

Of course! Many portable, battery operated, and lightweight coating thickness gauges are available for on-site and field inspections. They provide quick and accurate results and portable gauges are ideal for construction, automotive, and industrial environments.

You should not attempt measuring on surfaces that are dirty, oily, or rough, as these surfaces will not provide an accurate reading. Always calibrate the paint thickness tester and make sure to select the proper probe for the substrate as well. Proper execution will bring about consistency as well as trustworthiness to the readings.

Consistency in calibration is important to account for imbalances arising from wear and tear of the probe, probe pressure, variation from the environment, and fluctuations in daily usage. This is also necessary to maintain the best quality to various international standards.

Different types of substrates require different kinds of digital gauges. Magnetic gauges are for ferrous metals, eddy current gauges are for non-ferrous metals and ultrasonic gauges are for any non-metal composites like plastics. Careful selection of a gauge is the most important factor for obtaining accurate measurements.  

The dry film thickness is assessed after the coating is cured, while the wet film thickness is obtained immediately after the coating is applied using a wet film comb gauge. Dry film measurement is critical to ensuring that the coating applied matches the standards expected in terms adherence and polish. 

A coating thickness gauge measures film layers by identifying shifts in magnetic flux, eddy currents, or ultrasonic echoes as they penetrate the coating. The gauge calculates thickness based on the magnitude of these signals. This universally accepted approach results in quick, reliable, and non-invasive measurements.