Metallic Gold Sticker Paper note three points before output

Metallic Gold Sticker Paper note three points before output

 

I. Scanning color separation

The principle of scanner calibration is to adjust the scanner to faithfully reproduce the level information, color change and gray balance of the original manuscript. The specific method is to use a special emission or transmission color scale, the scanning software to adjust the value of the highlight, dark and intermediate value of the gamma. Adjust RGB or CMYK single-channel values, if necessary, so that the tone, color, and gray balance of the electronic image is consistent with the color scale.

 

The procedure is as follows:

1. Keep the scanner stable for more than 10 minutes after starting up, place the standard color code in the scanning area, start the scanning software, and scan with default parameters.

 

2. After the scanning is completed, use the probe to measure the color data of the gray ladder ruler in Photoshop. Adjust the highlight value and dark tone value in the scanning software according to the need, so that the first level of the gray ladder scale is between 250 and 255, and the 22 level of the dark tone is between 0 and 5. If the dark tone value is larger after scanning, the light and dark tone is not black enough. You can increase the dark tone value from 0 to a higher value, so that level 22 is equal to 5, or less. Of course, the same goes for white field scaling. Between level 19 and 22, the value difference is not big, roughly about 10, the dark level did not open, the level is compressed loss. This is determined by the performance of the scanner itself and has little effect on most manuscripts. For the darker level of the rich manuscript, it is recommended to use a drum scanner.

 

3. Adjust the intermediate gamma value to make the 11th level of the grey ladder scale about 125. If the level 11 value is too small, increase gamma; Otherwise, the gamma value is reduced.

 

4. According to the relationship between the RGB values of each level of grey ladder scale, adjust the values of the three in a single channel so that the values of each ladder scale in the three channels are roughly equal. If R=G=125,B=119, the gamma value of B channel can be increased to make it not yellow.

 

The scanned RGB image can be output only after the color separation is converted to CMYK. During this period, the image is also corrected for color separation.

 

Two. Graphics, image processing and group version

 

1. Setting of color separation parameters

This mainly includes printing ink Settings and color separation Settings.

 

(1) Setting of printing ink

① If the coated paper printing, the ink can be TOYO INKS or SWOP INKS. Other parameters can be determined according to the specific paper.

 

② dot gain refers to the increase of dot points at 50% of the median adjustment. If it is printed on coated paper, it is recommended to take between 12% and 15%; If it is printed on offset paper, use 15% ~ 20%; If it is printed on newsprint, it is 20% to 25%. The larger this value is set, the smaller the CMYK data will be after color separation.

 

③ Gray balance refers to the value of ink gray balance during printing. This value is available in every printing house.

 

(4) Gray image using dot enlargement. Click this item and the grayscale image will change to compensate for dot expansion. The larger the dot expansion value, the darker the display. The option also affects the conversion data of other modes to grayscale mode. For example, when converting a grayscale image from RGB, if this item is selected, the software will automatically call the dot enlargement value to compensate the value of the grayscale image. The larger the dot expansion value, the smaller the gray scale data.

(2) Color separation Settings

Select the separation set up option under filepreference.

 

① Color separation type There are two types of color separation, GCR and UCR. Choose one at a time. GCR is grey component replacement; UCR is the background color removal. The background color removal here is different from the previous background color removal on the generator, so the GCR mode is recommended.

 

(2) Determine the black version of the tone curve (black generation) when the gray component of the image is not much (such as landscape pictures, portraits, etc.), usually set the black version as the black version; If the image is high saturation, high contrast art photography, you can set the black version to a short height contrast black version; When there are many gray components in the image (such as old paintings), use a long black version.

 

(3) Different types of manuscripts should have different values, from 70% to 90%, generally 85%.

 

(4) tital ink limit indicates the maximum value of the sum of four color dots. Such as copperplate paper offset printing, take 340% ~ 380%; Newsprint is about 260%.

 

⑤ background color gain (UCA Amount) This value mainly increases the value of CMY in dark tones. For manuscripts with rich darkening levels, the value can be larger, such as 40%; On the contrary, smaller is better.

 

2. Color correction

Photoshop mainly processes the scanned images from two aspects: panchromatic correction and selective correction. For panchromatic correction, curves can be used to correct high and dark tones, taking into account the level and gray balance of the image. For selective color correction, necessary adjustments can be made to the local color blocks in the figure. The amount of adjustment can not be too large, otherwise easy to produce hierarchical fault.

 

After processing the graphics and images, you can use the group version software for group version. After the group version, you can carry out the output and release, that is, prepare the film.

 

Three. Output hair row

Output dispatching relies on RIP technology. Raster image processor, which converts graphics, images, and text information into a page language understood by a variety of large format printers or phototypesetters for output. It can control printing precision, color and format size.

 

No matter what kind of RIP, there are two technologies to convert electronic files into print language: one is color separation; Second, add net. Color separation is generally four colors, and sometimes there are more spot colors. RIP is divided into hardware and software. Hardware RIP is built into the printer phototypesetter or a dedicated hardware RIP chassis. Software RIP includes the software body and various device drivers. The main body of the software implements rasterization, and the resulting image file is sent by the specific device driver to the corresponding external device for output. Hardware RIP is generally not flexible. Dispatching machine can only be deployed, not used, and once the host problems, not good maintenance; The software RIP is flexible and can be used by the dispatching machine. If a host is faulty, you can reinstall RIP software on another host. Therefore, software RIP is more convenient to use.

 

Now there are two kinds of RIP on the market. One is the PSPNT RIP series of Peking University Founder. Another is Harlequin Express RIP.

 

Founder's PSPNT RIP is very handy when printing Photostat or wits generated PS files. Special PS file generation, speed is very fast. As long as the print with the picture path can be smoothly completed printing. But it generates the dot sometimes false, not real enough; It's a hassle to print Photoshop files on a MAC. Sometimes, it doesn't print at all. And the lower version, for the MAC printed files can not be color preview. This problem was not solved until the latest Founder Century RIP was introduced. But the lattice information of the pre-view time, but can not be stored. Harlequin's Express RIP generates a much more realistic and clear network. Whether it is a MAC or a PC, the layout of the file can be printed, and can be printed directly, without the need to generate PS file this intermediate link. Of course, it can't print the PS files that wits or Fly generates.