Consumers like it glossy, they love gloss - this is true for almost every industry, from the automotive industry to consumer electronics and children's toys. Regardless of the industry, a kind of glamor is associated with gloss as well as luxury and wealth. Studies suggest that humans' innate penchant for shine may be based on a biological need for water: the shinier an item, the more likely it is to "quench one's thirst."

From an industry perspective, luster can serve a very specific purpose. By definition, glossiness is an optical property that indicates how well a surface reflects light in a specular (mirror-like) direction - or how shiny or shimmering an object appears. Many industries prefer a glossy finish, while others require a more matte finish.

Why measure gloss?

Measuring glossiness during the manufacture of a product can improve the production process by identifying process issues, maximizing consistency, reducing scrap and improving overall quality. Surface texture, coating properties and paint application can all affect the appearance of a coating. While it is easy for the human eye to discern large differences in glossiness, e.g. Comparing a matte finish on a military object to a glossy red sports car, for example, minor differences in gloss are more difficult to detect but can still have a large impact on process control.

What is reflectance?

When light hits a surface, some of the light is absorbed and some is reflected. The reflected light is responsible for how the object is perceived. The type of reflection is generally related to the surface finish of the object. On a smooth, polished surface like a mirror, light reflects in the opposite direction to the angle at which it arrives; this is called "specular" reflection. On a rough surface, light is diffusely reflected at all angles and a relatively small portion of the light is reflected at the specular angle.

What is Percent Reflection (%)?

Reflectance is a measure of the amount of light captured versus the amount of light emitted and is expressed as a percentage. Gloss meters such as the PosiTector GLS can display both GU and percent reflectance directly on the meter.

What is a gloss value? What are gloss units?

According to ISO 2813, the gloss value is the ratio between the reflectance of the test sample and the reflectance of a polished black glass surface standard "having a refractive index of 1.567 at a wavelength of 587.6 nm in the specular direction", multiplied by 100. It is expressed in gloss units.

What is the Haze Index?

Haze is the appearance of a "milky" haze on reflective surfaces caused by microscopic imperfections in the surface texture. The Haze Index is calculated and is defined according to ASTM D4039 as the difference between the gloss values measured at 60° and 20°. PosiTector GLS 20/60 and PosiTector 20/60/85 are able to calculate haze when selected in the setup menu.

How is gloss measured?

Digital glossmeters like the DeFelsko PosiTector GLS glossmeter measure the surface with a calibrated light source and light sensor placed at opposite angles to each other. The degree of reflection is determined by comparing the amount of energy emitted by the light source with the amount of energy received by the sensor. The gloss is then calculated automatically.

The PosiTector GLS gloss meter has a built-in gloss standard. When the device is switched on or when the function is selected from the menu, the device automatically calibrates itself using the known gloss unit values of the gloss standard.

Choosing the best angle for gloss measurement

For most surfaces, the reflectance and gloss value increase as the viewing angle increases. This can often be seen with the naked eye: on the plastic case shown below, for example, there is little reflection when viewed from above. However, if the same suitcase is viewed from a greater angle (closer to the surface), a reflection can clearly be seen. A useful phenomenon to achieve higher measurement resolution on high gloss and matte surfaces.

To determine the correct gloss measurement angle, gloss is first measured at an angle of 60°:

• If the reading is between 10-70 GU, the object in question is considered semi-glossy. A measuring angle of 60° is ok. If the reading is greater than 70 GU, the surface is considered high-gloss and should be measured at a 20° angle. If the reading is less than 10 GU, the surface is considered matte and should be measured at an 85° angle be measured.

How to take gloss measurements with the PosiTector GLS gloss meter

The PosiTector GLS gloss meter is available in three models:

• PosiTector GLS 60° for measuring most gloss applications and is the preferred angle for semi-gloss PosiTector GLS 20°/60° for measuring high-gloss to semi-gloss and calculating Haze IndexPosiTector GLS 20°/60°/85° for measuring high- , semi- and matt gloss as well as for calculating haze

Gloss measurement with the PosiTector GLS gloss meter is quick and easy to perform:

It is very important to keep the gloss standard clean to verify the accuracy of the meter. Periodically, or when dirt or debris is visible, the gloss standard should be cleaned with the cleaning wipes provided.

Once the self-test is successful, the PosiTector GLS is ready for measurement.

Before turning on the meter, make sure the protective base plate is firmly seated on the probe. After power-up and with power-up calibration enabled, the probe automatically performs a self-test and calibration using the gloss standard built into the baseplate.

Traceable calibration certificates are included for both the probe and the gloss standard.

Remove the protective plate from the probe and place the probe on a firm, flat surface. Press the button on top of the GLS probe to take the measurement; the meter will now beep twice and a reading will be displayed.

Features of the PosiTector GLS gloss meter

The PosiTector GLS has multiple measurement modes and helpful features that make it suitable for almost any application:

• HiLo mode: for quick inspections or pass/fail checksDifferential mode: automatically calculates the difference between the current reading and the stored reference value*Normal scan mode: measurement and storage of up to 120 readings per minute*Statistics scan mode: continuous Measure and view real-time statistics, save each scan to memory*Alternative Calibration Standards: Save multiple calibration standards (tiles) for quick calibration adjustment

*Only available for PosiTector GLS Advanced models

As part of the modular PosiTector system, the PosiTector base units are compatible with any PosiTector probe and can be transformed from a gloss meter to a coating thickness meter, surface profile meter, climate / dew point meter and more by simply changing the probe. Other advantages include the shock-resistant 2.8-inch color touchscreen and the easy-to-use menu. PosiTector Advanced base units can be connected to a smartphone, tablet or laptop via WiFi or Bluetooth.

Manage gloss readings with PosiSoft Desktop Software

When the gloss measurement is complete, download the readings via the USB port or via WiFi if using a PosiTector Advanced base unit. When the meter is connected via a USB cable, you can quickly and easily download and view stored readings as professional PDF reports and print them using PosiSoft Desktop Software (for PC and MacOS). Fully customized reports can be created, eg to conform to standard formats or layouts.

Conclusion

Gloss measurement is often done for aesthetic reasons, but gloss measurement can also have a major impact on process and quality control. The PosiTector GLS gloss meter is fully equipped to handle many gloss measurement applications.

Watch the PosiTector GLS Gloss Meter video or visit the product page for more information.

Video transcript of the PosiTector GLS Gloss Meter video above

How to measure gloss with the PosiTector GLS gloss meter from mtv messtechnik.

Gloss is an optical property that indicates how well a surface reflects light in a specular direction.

It refers to how shiny or shimmering an item appears, which affects its aesthetics and perceived value.

The light is reflected at the angle of incidence on high-gloss surfaces. The light is scattered diffusely in all directions on matt surfaces.

Several factors can affect a product's gloss, including texture, coating properties, and paint application.

Gloss measurements can identify process issues and defective parts, maximizing consistency, reducing waste and improving quality. Gloss is usually measured and reported in Gloss Units, or "GU", which stands for Gloss Units, as defined in standards such as ASTM D523 and ISO 2813. In addition, some gloss meters, such as the PosiTector GLS, can measure reflectance and haze index.

The degree of reflection is a measure of the amount of light captured in relation to the amount of light emitted and is expressed as a percentage.

Haze is the appearance of a "milky" halo or haze seen on reflective surfaces due to microscopic imperfections.

The "Haze Index" is measured according to ASTM D4039 by subtracting the 20° from the 60° specular gloss measurements.

Due to the wide range of gloss values, different measurement angles are used to achieve the best resolution for matte, semi-gloss, and gloss samples. The 60 degree measurement angle is the recommended starting point and is used to measure many common surfaces such as interior wall paint, furniture, packaging materials and plastics.

Paints that have a value of more than 70 GU at a measuring angle of 60 degrees are considered high gloss and should be measured at a measuring angle of 20 degrees. These finishes are commonly seen on automobiles, traffic signs, and other applications where a reflective or specular finish is desired.

Surfaces that have less than 10 GU at a 60 degree measurement angle are considered matte and should be measured at an 85 degree measurement angle. Gloss measurements in this range are commonly seen on products such as fabrics, leather, and military items.

The PosiTector GLS Gloss Meter is the ideal tool for quality control professionals. Three probe models are available.

The PosiTector GLS 60° is suitable for most gloss applications and is the preferred angle for measuring semi-gloss.

The PosiTector GLS 20°/60° is ideal for high to semi-gloss applications and has the ability to calculate the Haze Index.

The PosiTector GLS 20°/60°/85° is suitable for all gloss applications - high gloss, semi-gloss and matt. It is also able to calculate the Haze Index.

After switching on, the probe performs an automatic self-test and calibration using the calibration standard integrated in the protective base plate. A traceable calibration certificate for both the probe and standard is included.

For some applications it may be desirable to calibrate the probe to a different calibration standard. Easily add and manage up to 99 different standards.

The robust all-metal probe is designed for long-term stability and a long service life. It is connected to the PosiTector base unit via a cable, making it ideal for measurements in confined or difficult-to-access environments.

PosiTector bases are compatible with any PosiTector probe and quickly convert from a gloss meter to a coating thickness meter, surface profile meter, climate meter, dew point meter and many more.

Two basic devices are available:

The PosiTector Standard base unit is compatible with all PosiTector GLS probes, has a HiLo alarm mode and can show statistics on the screen during the measurement, e.g. B. Average, standard deviation, min/max and number of readings, with up to 1,000 readings can be stored.

The PosiTector Advanced base unit offers all the functions of the PosiTector Standard base unit plus the storage of up to 250,000 readings in up to 1,000 blocks and additional functions such as scan and difference mode:

By default, the PosiTector GLS is able to take one reading per second. In normal scan mode, the device can continuously measure and store up to 120 readings per minute. With Statistics Scan, the sonde continuously measures and displays scan statistics in real time, with only the statistical summary for each scan being stored in memory. For quick inspection or pass/fail checks, HiLo mode visibly and audibly alerts the user when measurements exceed user-specified limits.

In differential mode, the difference between the current reading and a stored reference value is automatically calculated - ideal for comparing the results with a known target value.

Gloss measurement with the PosiTector GLS gloss meter is quick and easy:

Turn on the meter using the center navigation button.

The PosiTector GLS automatically performs a calibration each time the meter is turned on. Make sure the probe is inserted into the included protection plate with built-in calibration standard.

Periodically, or whenever dust or dirt is visible, the Gloss standard should be cleaned with the cleaning cloths provided. Keeping the standard clean is critical to the accuracy of the gauge.

The PosiTector GLS is now ready for measurement.

Remove the protective base plate from the probe and place the probe on a firm, level surface.

Just press the button to take a measurement. When a measurement is taken, the meter will beep twice and the reading will be displayed.

When the inspection is complete, you can download the readings via the built-in USB port or alternatively via WiFi or Bluetooth if you are using an Advanced gauge.

Once connected, you can quickly and easily download, view and print saved readings in professional PDF reports using PosiSoft Desktop.

Fully customized reports can be created to match existing paper forms or layouts.

The new PosiTector GLS Gloss Meter is the simple, durable and accurate way to measure gloss.

With an easy-to-use interface, high measurement speed, onboard memory and simple reporting solutions - alongside the well-known good build quality and excellent customer service -

the PosiTector GLS gloss meter is the best choice for gloss measurement.