How to accurately see samples in printing

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How to accurately see samples in printing

1 the intensity of light directly affects the judgment of the color of printed samples

the intensity of light not only affects the brightness of color, but also changes the appearance of color. At ordinary times, we observe a light receiving cylinder. The light facing side is bright, and the backlight side is dark. The combination of light and shade is the middle tone. The same object is positive color under the standard light source. If the light gradually becomes stronger, its hue will also change to the bright hue of transmitting data in real time and comparing the data during the experiment. The brightness is enhanced to a certain extent, and any color can turn white. The reflective point of black porcelain is also white, because the light at the reflective point is concentrated and strongly reflected. Similarly, the light gradually decreases, and various colors change to the hue with low lightness. When the light weakens to a certain extent, any color will turn black, because the object does not reflect any light is black. Table 1 shows the influence of light intensity on color. The sample viewing platform in the printing workshop must meet the requirements. Generally, the illumination is required to be about 100lx in order to correctly identify the color

2 there are differences between viewing samples under colored light and sunlight

in the actual production process, most of them work under the irradiation of power supply, and each light source has a certain color. This makes it difficult to correctly judge the color of the original or product. When viewing the color under color light, the color change is generally the same color becomes lighter and the complementary color becomes darker, for example: viewing the color under red light, red becomes lighter, yellow becomes orange, green becomes darker, green becomes darker, white becomes red. Viewing color under green light, green becomes lighter, green becomes lighter, yellow becomes green, red becomes black, and white becomes green. Looking at the color under yellow light, yellow turns light, magenta turns red, blue turns green, blue turns black, and white turns yellow. Viewing color under blue light, blue becomes lighter, blue becomes lighter, green becomes darker, yellow becomes black, white becomes blue. In the printing workshop, Generally, the color temperature is high ("Honeywell 1 is at the forefront of military bulletproof technology 3500~4100k") , the fluorescent lamp with good color rendering coefficient and slightly deformed cast iron specimen at last is used as the sample viewing light source, but it should be noted that the fluorescent lamp is slightly blue purple

3 the results will be slightly different if you look at the sample first and then the print and then the sample

you will feel different when you look at one color twice. This phenomenon is called sequential color contrast reaction. Why is there a sequential color contrast reaction? This is because looking at the color first makes the color nerve fibers excited, and then looking at other colors immediately. Other color nerves are soon excited to cause color sensation, while the color nerves that look at the color first are in a state of inhibition after excitation, and then excited slowly, causing a negative hue reaction. This reaction, coupled with the hue of the new look color, forms a new color, so it changes the look color. And the hue of the change is still regular, which is to change the complementary color of the first look color

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