Handmade Hinged Lid Cigarette Box Specification Of Color Management in Digital Proofing

Handmade Hinged Lid Cigarette Box specification of color management in digital proofing

 

The core problem of color management is to determine the true color meaning based on a known color information, such as RGB or CMYK value, and to reproduce the true color perception on another device by changing the color value transmitted. The effectiveness of color management depends on the accuracy of the characteristics file of the device being used. If the characteristics of the device change, the characteristics file will no longer be accurate and we will not be able to accurately copy the colors we want to copy. Therefore, in order to maintain the consistency of product color in the long term production, it is necessary to standardize the operating environment, which is also the premise of color management technology to play a role.

 

Calibration is the basis of color management system. Calibration is the method of adjusting each device (monitor, scanner, proof machine, etc.) to the defined standard state, the purpose is to achieve the consistent behavior of the device, is to describe it correctly in the characteristics of the device, so as to carry out the correct color management work.

 

I. Implementation procedure of color management in digital proofing

Second, establish a standard operating environment

 

The standardized operation should start step by step from the beginning. Only in accordance with the standardized and standardized operation process, the whole digital proofing process can be based on evidence, in order to effectively improve the proofing quality, and realize the perfect match with the printing proof.

 

1. Specifications of printers

The quality of digital proofing is closely related to the printing software, printer, ink and paper. Only by determining the standard parameters of various processes, the equipment can achieve a good working state, and it is possible to achieve the stable process conditions required by color management.

 

① Experimental conditions

EPSON STYLUS 10600 color inkjet printer with EYE-ONE Spectrophotometer;
Founder smooth flow color management software, ICC file generating software Profile maker5.0;
EPSON digital proof paper, EPSON's original six color ink.

 

② Experimental procedure

Establishing basic printer linearization, which determines the physical properties of the paper and ink acting together to achieve the greatest possible color density with the smallest possible amount of ink, provides the basis and optimization features for the creation of the ICC profile of the printer paper, thus establishing the basis for color management.

 

Take the square smooth flow as an example, that is, print the four-color grey ladder ruler directly, and test it with a spectrophotometer, and then generate the basic linearity of the printer directly. Then print the total amount of ink, from the printed proof to determine the total amount of ink printer.

After the basic linearization is done, the ECI2002 color scale is first printed and the L*a*b* of the color block is tested with a spectrophotometer. Then the ICC Profile reflecting the suitability of printing is generated using profile maker software.

 

2. Specifications for printing presses

The color management of digital proofing must first establish a standard printing status, on which the generated ICC Profile can accurately reflect the color performance of the equipment and printing materials, so that the resulting digital proofing is truly practical in the actual production.

 

① Prepress process specification

The film output of the phototypesetter should meet the quality standard of the output film. Including the normalization of process parameters such as phototypesetter exposure, linearization cycle, washing time, washing temperature, compensation amount, field density, fog degree and so on. The required error of each point of the film output is ± 1%, the maximum density is ≥4.0, and the output dot curve is straight.

 

In addition to the phototypesetting process should be considered, the printing process also includes the adjustment of exposure. The adjustment of exposure is mainly determined by the grey ladder, microline block and dot performance on the printing control bar (mostly FOGRA). The presence of 3%-98% outlets is preferable.

 

(2) printing process specification

Printing process specifications mainly include: paper ink performance parameters, ambient temperature and humidity, plate blanket selection, printing color sequence, printing speed, printing pressure, field density.

 

Profile maker and eye-one spectrophotometer were used to test L*a*b* values of various color blocks of ECI2002 color scale printed under standard conditions, and ICC profiles reflecting the suitability of printing were generated.

 

Three, the analysis of color management application

The ICC Profile that reflects the printing process characteristics and the ICC Profile that reflects the color printer characteristics are put into the square flow, and the color management module (CMM) in the flow is used for file matching, so that the digital proofing can simulate the final printing effect. The ICC Profile is created to reflect the final effect.

 

If we are not satisfied with the results of the proofing system used, we can choose a paper whose printability is somewhere between the characteristics of various paper and use this paper/ink/press combination as the target value to create a characteristic document. Once the press has been characterized under these conditions and the target value for the paper/ink/press combination has been established, the proofing equipment can be characterized against this target value. When proofing, the color is transferred from the press characteristic file to the characteristic file of the printer, and the dot expansion changes brought about by different papers are compensated by curves on the phototypesetter or direct platemaker, so that different proofing effects can be satisfied using this single press characteristic file.

 

However, only one color space conversion cannot achieve accurate color conversion. According to the actual situation, the ICC file of the printer needs to be modified and edited several times. You can modify the dot increase rate, gray balance data, UCR and GCR parameters, the total amount of ink, etc., and also adjust the four color curves of yellow, color, blue and black respectively. In order to ensure the consistency of simulation effect, use for a period of time to re-measure the data, do a black version curve slightly adjusted new feature file.