Lightness and Brightness and Other Confusions

Examples of perceptual concepts related to colour
Basic colour terms: red, blue, green, yellow, white, black, brown,
grey
Conventional colour names and colour names in e.g. fashion and
clothing industry: aqua, buff, Burgundy, coral, cream, light blue, olive
green, turquoise
Terms referring to artistic work: primary colour, secondary colour,
tertiary colour, tint, shade, broken colour, pastels, earth colours
Perceptually specified colour terms: hue, value, lightness, whiteness,
blackness, nuance, chromaticness, chroma, elementary colour,
mode of appearance
When it comes to scientific work, the concept colour has to be specified. One
definition is that given by the Natural Colour System, Swedish standard for
colour notations. It is entirely based on visual experience and defines colour
as that which the human being in any given situation sees as colour, and
which makes it possible to distinguish objects and fields 49 using their colour
differences (colour discrimination), and to characterise objects and fields
with the help of, for example, colour names (colour identification) (Hård et
al. 1996). Starting from this definition we can make further specifications of
colour as a visual quality.
With attentive seeing we can identify the perceived colour (Fridell Anter
2000, p 23) of a specific surface or object, a quality that is not constant but
varies with the viewing situation and between persons. The perceived colour
can be described and categorised only by attentive observation and cannot be
measured with photometric, colorimetric or any other instruments. (Fig. 8)
Depending on the detail of level of our attention, we can concentrate on the
perceived identity colour, that is the main colour impression of a surface that
is perceived to be uniformly coloured, or on the perceived colour variations
that for one reason or another can be found within the ‘uniform colour’, if we
look for them carefully enough. (Billger 1999, p 11). We can also experience
that which is commonly referred to as the ‘real’ colour of the surface. This
’Objects and fields’: from the Swedish föremål och fält. ’Field’ here refers to the same
concept and phenomenon as film colour (Flächenfarbe) in David Katz’s definitions of
the eight modes of appearance of colour. (Katz 1935).
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