Techniques and Key Points of Reproduction (4)

5, White field (high light) set of five methods.

(1) The method of setting the gray scale.

The standard setting method should be set using the gray ladder. The transmissive document uses a first ladder of a grayscale or a step corresponding to a high optical density of the document. Reflected manuscript with the first step white block reflecting ash ladder feet.

(2) White block, white paper setting method.

Transmit the manuscript with the white block in the transmissive color standard, the color photo uses the white side of the photo paper or the white block of the photo paper, the printed manuscript uses the smooth smooth white paper with the same thickness. The advantage of setting with grey ruler or photo paper white or white paper is:

a. Since the whiteness of the gray scale and white photo paper is relatively pure and neutral, it can accurately reproduce the change of the subtle color levels in the original highlight white.

b. Because the scanning head has a small number of holes, the accuracy of the selection point is high, and the output voltage is stable and there is no jumping phenomenon when using a ruler or photo paper white setting.

c. Because the density of the ladder and the photo paper white is the smallest, it is set to 0% of the three primary color version, so that the high gloss white color dot values ​​of the image can be accurately reproduced, if not a ladder or phase of the gray ladder. Using paper white as a reference point, it is difficult to determine how many dot values ​​should be placed in the image for high-gloss white. For example: M656, 636, 6200 series extensions, use the AUTO key to set 0% on the white block; Ever smart pro platform scanner, set pt set to 0%, can accurately reproduce the fine level of the original highlight white and Its outlet value.

d. Repeated settings can be made for the same original to achieve consistency.

(3) Extreme highlight setting method.

Sampling points were selected at the extreme highlights where the original does not require a gradation, and the trichromatic version was set to 0%. As with the photographic white setting method, it is possible to accurately reproduce high-light white color dot values.

(4) Neutral white setting method

Sampling points are selected in the original part of the neutral white part of the required level, with the minimum density of the color version prevail, set with the AUTO key, such as C, M, Y is 5,3,3,6,4,4 and so on. Gravure is 7,5,5,8,6,6 and so on.

(5) Inverse color setting method

The sampling point is selected in the brightest part of the original highlight, because the opposite color value of the hue is close to the white value, and the opposite color of the hue is set to 0% or the required dot value. If the M565 extension can manually set the 0% or desired dot value using MANUTL, such as the solar, steel flower type manuscripts, the C version is set to 0%, then, the Y, M color version will appear a certain percentage of the dot value . The white field (highlight) setting methods described above can reproduce the highlights and highlights of the original. This is suitable for most manuscripts and can be easily grasped.

In addition, M656, 636, 6200 series extensions can also use CAL28 calibration method, as long as the C, M, Y tricolor version enter the same high optical density value to get the ideal basic white settings. As shown in Table 2:

Table II

Transmitted text input density value Reflected text input density value

Original density contrast standard 0.30-0.40 0.03-0.06

The original density is thin 0.15-0.25 0.00-0.02

The original density is boring 0.45-0.60 0.08-0.20

Another example is the highlight setting of the Ever smart pro platform scanner in three ways:

(1) AUTO mati setting method:

Keep the original white paper color, balance only does not light up, such as the set value on the white block is C8, M6, Y6.

(2) set white pt setting method: (most of this method).

According to the white paper, automatic correction, and for brightening, such as set on the white block is: C2, M, Y1, this setting method selects sampling point, must be neutral white or to be made into white section.

(3) White Density setting method:

If the original has no highlight white, it is very good to use this to manually enter the white field density. The scanner highlight setting density range of 0.00 ~ 0.80, according to the original situation to set the corresponding density value, for example:

Standardized setting method, color photographs:

The original density standard setting is 0.18.

The thinness of the original density setting is 0.16.

The dark density settings for the original density are 0.20, 0.21, 0.22, and 0.23.

If you use the set white pt setting, the white paper still has color cast, you can use Remove case method to correct.