Appearance Measurement – How does Colour and Gloss affect our perception?

The importance of understanding how Colour and Gloss affects surface appearance

When light strikes and object, the light changes. If the change is measurable, reproducible and diagnostic it can be used for non-destructive measurements and testing.
This allows us to identify certain properties of the object. One of the properties we are able to detect is Appearance.

But what constitutes appearance?

The appearance of an object can often be the only instant indication of the quality of that object. No matter the object, whether it is paint, plastics, automotive components, building materials or textiles, appearance of that object is made of three primary characteristics:

  1. Colour
  2. Gloss and Surface effects
  3. Other effects – Such as metallic or pearlescent particles

COLOUR:

We have seen that the Colour of an object requires three elements in order for us to perceive that object. The elements that we require are LIGHT, an OBJECT and an OBSERVER. Without any one of these elements we cannot determine the colour.

Humans perceive colour with our eyes and the information is translated by our brains. The light that is reflected off an object has defined wavelengths that our brains interpret as that colour. All light that we do not see is absorbed by the object. Although this works to determine Green from Red, it is more difficult to distinguish between two shades of Red and even more difficult to communicate that colour to others. If you close your eyes and think of the colour SCARLET, what do you see?
This would change from person to person and we would end up with different descriptions of what should be the same colour.

Our customers use Konica Minolta colour measurement solutions to accurately determine the colour of their products. These instruments work in a similar way to our eyes. They have a LIGHT SOURCE, an OBJECT and a DETECTOR that allows them to measure colour and appearance. These instruments offer an objective way to compare and communicate colour by plotting the data on a C.I.E Colour Space such as L*a*b*.

GLOSS:

Just as all objects have colour, all objects have a certain amount of gloss. Gloss is an attribute of a surface that causes them to either have a shiny or matte finish. Regardless of the appearance of an object, it contains some level of gloss.

Gloss of shiny, newly polished sports cars would have a higher gloss value than a living room wall coated with matte paint.

Gloss also influences the appearance of a product. In general, if we have two objects with the same colour but different gloss values, we can expect the object with the higher gloss to appear darker or more vivid than the other object.

OTHER EFFECTS:

Effects such as metallic or pearlescent particles also influence the way we perceive an object. Shiny metallic particles in automotive coatings reflect a large amount of the light that is shined onto the surface.

These particles are actually little flat flakes that act as mirrors to reflect any light they receive in the direction they are aligned. If we have a coating where the flakes are not consistently aligned we will not have the glittering effect we might be looking for. Perfectly aligned flakes reflect light consistently across the surface.

*Arnold Renderer

To measure metallic effects, we require more advanced instruments than to measure Colour or Gloss. The Konica Minolta CM-M6, multi-angle spectrophotometer measures a surface at 6-angles which reports colour at each angle as well as a so called Flop Index. This index allows us to understand whether these flakes are aligned consistently or not. All of which influence overall appearance.

For the most part, metallic effects are more challenging to control, especially with regards to colour matching. We will therefore focus on monitoring colour and gloss and how these two properties relate to e

THE RELATIONSHIP BETWEEN COLOUR AND GLOSS:

As previously mentioned, an object with a higher Gloss reading may appear darker or more vivid to observers. While low gloss surfaces appear to be lighter in general

It is therefore important for companies to try and control both aspects of appearance, as although 2 objects may be the same colour, if they have different gloss readings they will appear different.

High Gloss Surface (Left) VS Low Gloss Surface (Right)

Controlling both Colour and Gloss is important to accurately interpret the appearance of a surface.

HOW CAN WE CONTROL BOTH COLOUR AND GLOSS?

As soon as we say that Gloss is an important aspect of appearance, we are asked how to you measure gloss and whether companies might need multiple instruments to measure both colour and gloss?

Companies in the plastics, paint, automotive and building materials industry will know that although they manufacture products that are the same colour, if the gloss changes, their products appear noticeably different.
This can cause arguments between customers and suppliers because although all parties may have measured the colour of their products and they have similar L*a*b* values, differing gloss values cause deviations in appearance.

Konica Minolta have found an all-in-one solution that mitigates these problems and allows companies to measure both Colour and 60° Gloss in a single handheld instrument.

To schedule a practical example of this instrument, kindly complete the contact form here and request a practical example: