Specular Component Included (SCI) vs. Specular Component Excluded (SCE)

In various colour measurement applications, you may notice that the apparent lightness of a sample differs based on its glossiness. For example, the colour of a glossy blue object seems more vivid than a rough-textured object of the same hue. Two samples with different surface textures can be viewed as different colours.

Spectrophotometers measured the reflected light from a sample. These precision colour measuring devices measure the body or diffuse reflectance and can include or exclude the specular reflection component. Determining the correct Specular Component Excluded (SCE) or Specular Component Included (SCI) modality to use in your situation is critical. The best option for you depends on your application and requirements. Therefore, it is crucial to understand the modality that works best for you.

Specular Component Included, abbreviated as SCI or SPIN, and Specular Component Excluded, abbreviated as SCE or SPEX, provide different information about the measured specimen. What is SCI versus SCE, and which option best fits your application? Read on to discover what both terms represent and how you can use them.

What Does ‘Specular Component Included’ Mean?

When you need to measure the total colour, you’ll probably want to use SCI. This method measures the spectral reflection component and the reflected body or diffuse component of a sample.

The SCI measurement determines total colour without being affected by a sample’s surface condition, for instance, polished or rough. When formulating recipes to match exact colours, SCI will typically be your best option because it measures the total reflected light from the sample.

Although this makes sense in the laboratory, it doesn’t work well on the production floor because it does not correctly assess the colour appearance. Consequently, two parts can have identical colour values, but they don’t look alike!

What Does ‘Specular Component Excluded’ Mean?

An instrument measuring colour in the SCE measurement modality excludes the spectral reflection component in its analysis. The SCE measurement provides a better assessment of the colour appearance attributes of the sample. We perceive the colour appearance of objects in much the same way.

When you need to measure the colour appearance of an object, SCE is the preferred method. This option is sensitive to surface conditions and measures the sample’s colour appearance to the human eye. With this method, you’ll be able to analyze the products’ colour appearance. SCE is ideal for quality control evaluations, aesthetic appearance, and maintaining surface quality during manufacturing.