Light is electromagnetic radiation from, so the light is part of the electromagnetic spectrum from the expression. The human eye can observe the spectral range called to see light, from a long band of the red light to a short wave segment of the LanZiGuang. Due to the human eye to see light color is only visible light waves within the scope of the a specific wavelength of light, so the light to observe the environment conditions observations have very big effect. If matches the color is observed during the day, and the match colors on fluorescent conditions get, then the match and not really accurate matching.
In addition, observe the turnover of target environment also to looking at the image color have influence. For example in the dark background and a light background see the same picture get colour feeling is different. This to customers in displaying sample questionnaire opinion, more important, to ensure the best possible customer observation conditions and printing ink process to build the consistent environmental conditions, or, to change the production of light condition, and customer's observation conditions are consistent.
The observer can be human observer, also can be a color measurement equipment (such as spectrophotometer)
Producers or equipments, instruments, can do it in different time see the same kind of image. Why is this?
First from human oneself to start. Human visual can distinguish ten million colors, an individual's psychological condition affects his or her on the color of feeling. When a person in healthy state, observing the color of the tiredness and sick or he is in the mood is low got the feeling is not the color with; Adults and children feel the feeling is not the same. And, specific kind of people to one a wavelength range of color changes to the sensitivity of the inferior, some even color blindness patients. Therefore, judge a color is correct or not, with the more personal visual feature for the foundation.
Color measurement equipment such as spectrophotometer, is measured by the reflex the light from objects, in a simulated 3 d color model is also called color space, with a set of color matching the form of the stimulus. In the measurement of the process, each equipment is in some given conditions after correction, complete the color sample color measurements. The given conditions including lighting conditions or light source type, view, whether to consider the influence of gloss, etc.
In theory, in the same environment conditions for the different equipment measurement results, in color space with the same color matching performance. But in fact, different equipment is between the genotype, the result is also different, even the same device itself, in not change any conditions, continuous two measurement results can also be different. In most cases, these subtle differences to the result too is not affected, but in different conditions by different equipment or the colour of tolerance is too hours, we have problems. Although printing department and customer may use the same equipment, but, because we can't guarantee that the equipment and the correction in the same way after processing observe colour, a complete measurement, so often will produce the difference. For example, rules or set of color, the color sample of the measure considering luster factors, while printing personnel in observation colour match, color sample of measurement and did not consider gloss factors, so, although the macroscopic observation to the matching of the results can be accepted, but from the instrument measuring results look would be unacceptable. Therefore, matching the computer produce a kind of particular tolerance range of color, ensure measurement equipment and setting color equipment used in the same environment observation is very important.
Color measurement in color matching plays an important role in, the measured results can produce a lot of useful information, can be in color space directly expressed by matching the color position, for reliable matching help. However, in some cases, although the measurement results look, matching the effect is very good, but in the visual effect or artistic effect on look is not ideal. This is because in the color matching evaluation of human visual still occupy the central position, so not only to consider measuring tool in the role of color matching, consider human visual's subjective feeling the effect of sex.
When fully consider the factors involved in observation target and observe the influence of the environment and see the subject (measurement equipment and human) after the role, the color management easy, along with to understand and implement the variables of the effective control, makes a headache, color matched work easier and efficient. Believe in the near future, to the color control ability will be strong.