Colorimetry is The Only Solution For Electronic Manipulation of Color

As described in " Functioning Principle of Vision " color is a sense impression which is determined by a variety of physiological factors. In physics color does not exist. The energy rays of light are colorless. Consequently, the energy rays of color stimuli are colorless, too. Any teaching or written matter to the contrary is provably wrong !

Mastering color in a technical way is only possible with the help of physics. It is always the matter of manipulating a color stimulus with the aim to induce the visual organ to produce determined color sensations.

Colorimetry is used for the physical analysis of a color stimulus and to calculate from it the basic spectral tristimulus values X, Y, and Z. The basic spectral tristimulus values X, Y, and Z relate to the spectral sensibility of the three cone types on the retina of the human eye. The colorimetrists reached an international agreement to use the CIE system. In the past this system has been modified in many occasions. Electronic communication is based on the CIE Lab version.

These basic spectral tristimulus values are used to calculate the code which would induce the visual organ to produce determined color sensations. In general, there is no alternative to this procedure.

Still, it is a serious problem that the CIE system is based on arbitrary assumptions of the sensibility of the three cone types which do not correspond with reality. Based on his own research, H. Kueppers established that the maximal sensibility of the three cone types are not where the CIE systems is assuming, but at 448 nm for B, at 518 nm for G, and at 617 nm for R. In view of the described problems one can easily imagine how difficult, maybe impossible, it is to obtain an accurate color reproduction at the end of an electronic process.

Actually, colorimetry should put itself on an entirely new basis. The assumed maximal sensibility of the three cone types should be changed and optimized. Besides, one should part with the RGB ideology and take into account the scientific findings of the new Kueppers' Theory of Color. The physical analysis of the color stimulus should lead in electronic synthesis to a four-value code, reflecting the subsets of the four Basic Colors which at the most could be involved in the composition of one color shade. Only then could "color management" be properly used and processes be controlled in a way that would enable working with either Chromatic Structure or Achromatic Structure or any intermediate stage, as wanted or needed.

However, such a change in the basic philosophy concerning the electronic reproduction processes will be anything but easy considering the worldwide distribution of the current electronic communication media .

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