Natural paints do not look the same as plastic paints.
There are scientific reasons for this which are fascinating but complicated, so in summary, for those who want to understand more.....
- How we see pigment
We do not see colours made from natural pigment and synthetic dyes in the same way as light is reflected from them very differently.
- Colour and how we perceive it
The science of colour in paint making is about paint ingredients - how the natural paint is made, the behaviour of light and how the colour spectrum works with the human eye.
- Measurement of colour
Attempts to measure and classify colours according to human perception has a long history, however since the invention of photo-spectrometers clear and objective measurement of colour can be achieved.
- Our natural pigments
With an understanding of the physics of light and colour we can examine how paints and coatings are coloured and how different types of colouration are achieved.
- Texture and colour
If the surface of the sample is very smooth, light will be reflected from that smooth surface like a mirror at the same angle and with the same spectral range. This affects the appearance of the colour, the higher the gloss the darker the colour appears whereas a textured surface (matt) with the same pigmentation will appear to be of a lighter shade.
- Other influencing factors on colour
- Scattering of light by pigments
- Transmition of light through the paint film
- Scattering coefficient of a pigment
- Pigment load of a paint film
- Thickness of the paint film
- Metamerism – Metamers are colours that can look the same under one set of conditions but different to one another under others. When the spectral curve of two colours crosses in at least 3 places metamerism is likely. Under different light conditions the difference in colour becomes apparent. This is why synthetic colours can look quite different in artificial light as opposed to daylight.