Lightness and Brightness and Other Confusions
Lightness and Brightness and Other Confusions
Lightness and Brightness and Other Confusions
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measured either trichromatically with a colorimeter or, for an even more<br />
precise result, with a spectrophotometer. Both methods can instantly reveal<br />
colour differences that are hard to detect with the naked eye. Another possibility<br />
is to use a visual colour matching system such as Munsell or the NCS. In<br />
the case of measurement, the meter is placed over the target, a calibrated<br />
light flashes to illuminate the target according to very exact preconditions,<br />
<strong>and</strong> the reflected light is analyzed into components of spectral energy emission<br />
by the meter’s microprocessor. 87 . The result is either a series of three<br />
numbers indicating the proportions of short, medium <strong>and</strong> long-wave radiation<br />
as detected by the human eye (colorimeter) or a series of some 40 or<br />
more numbers (depending on the precision required) indicating the presence<br />
of radiation at specific wavelength intervals, weighed against a theory of the<br />
spectral sensitivity of the human eye (spectrophotometer). In the case of<br />
visual colour matching the target is compared to a sample from a colour system’s<br />
st<strong>and</strong>ardised collection. This too is ideally done under st<strong>and</strong>ardised<br />
viewing <strong>and</strong> lighting conditions.<br />
These kinds of colour measurement provide highly accurate information<br />
about whether a colour is the same or different than a sample or another<br />
target. But does it tell us what is the ‘real colour of the object’? If by colour we<br />
mean what humans see in the real world here <strong>and</strong> now <strong>and</strong> in context with<br />
other colours, the answer must be no. Measuring data are abstract series of<br />
numbers that have no connection to the experience of colours in context.<br />
Colour sample matching is a step closer to real experience, but it still misses<br />
out on the contextual issues in perception. As mentioned earlier, colorimetric<br />
<strong>and</strong> spectrophotometric measurement, as well the underlying CIE-system,<br />
were in fact never developed for precise colour identification, but for the<br />
purpose of attaining highly precise information about colour differences.<br />
Visual colour systems, such as the Munsell <strong>and</strong> NCS systems, on the other<br />
h<strong>and</strong>, were developed for the very purpose of providing a reliable system for<br />
identifying, comparing <strong>and</strong> communicating colours of objects <strong>and</strong> surfaces in<br />
the real world. Visual colour systems, with their collections of systemized <strong>and</strong><br />
st<strong>and</strong>ardized colour samples, are no doubt the best way to go about this<br />
task. 88<br />
It was mentioned in the section on vividness of colour (p. 84–91) that colours<br />
can be examined either as non-related or related phenomena. An example of<br />
This may seem like a fairly straightforward physics <strong>and</strong> maths task, but there are<br />
many hitches <strong>and</strong> obstacles to be avoided before anything near a ‘correct’ reading is<br />
obtained. Just consider the difference in appearance <strong>and</strong> reflectance pattern of a piece<br />
of red fabric <strong>and</strong> polished red metal. The same kinds of difficulty are involved in visual<br />
colour matching.<br />
Painting or high-quality colour photography can render the contextuality <strong>and</strong> hence<br />
the general impression or ”atmosphere” of spaces <strong>and</strong> environments much better than<br />
any colour notation system, but this happens inevitably at the expense of accuracy in<br />
real colour, as explained in the above example of the green apple.<br />
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