Fred Kuo :: Blog

This time, I tried to switch my most frequently used CT10 tool to work in mobile mode. However, there are still differences in performance between the mobile phone and laptop, and my mobile program skills are still quite basic. I could only crudely stack the limited programming components I knew and barely create a usable version.

"Fig. A brute-force stack of code exceeding 5000 lines, barely creating a usable working model.

Here, let me briefly introduce the functions currently available on the mobile app.

After capturing the numerical values, these numbers are applied on two levels.

The first level is print quality scoring, which evaluates the finished product based on the solid CMYK color value, 50% tone value, and gray balance value."

Fig. The main screen displays the Lab values and density values of 10 color patches. For the 50% color blocks, the tone value is also displayed.

For the scoring section, three printing specification options are currently available: Fogra39, Fogra51, and CRPC6. As shown in the data in the following figure, the difference between Fogra39 and CRPC6 can reach up to 6 points for the same set of data. The target values for the  solid CMYK  are not significantly different, but the TV target values differ greatly, with CRPC6 having a 2% higher increase in CMYK TV at 50% than Fogra39."

Fig. The current version provides target values based on three printing standards: Fogra39, Fogra51, and CRPC6.

Based on  the data displayed on the main screen, the next layer of functionality is to provide operational instructions. Simply clicking on a color patch on the main screen will bring up the corresponding operational instructions for that color patch.

As an example using the figure above, the operational screen for C ink shows a current density of 1.45 and a color difference of 6.12. When the density is reduced to 1.21, the color difference will decrease to 2.81, so the operational instruction is to reduce the ink by 0.24. Throughout the display system, when values are not within a tolerant range, a red background warning will be displayed , so the operation is to work until there is no red color block. The operation is intuitive and the interpretation is fast

The operational instruction screen for M ink shows a current density of 1.59 and a color difference of 5.37. When the density is reduced to 1.34, the color difference will decrease to 2.1, so the operational instruction is to reduce the ink by 0.25.

Y ink operation screen shows a current color difference of 4.76, and the best color difference prediction is only up to 4.72. Therefore, two red block messages indicate that the yellow ink cannot be operated within the acceptable range, and only by replacing the ink can it be attempted. Otherwise, it can only be operated up to a color difference of 4.72.

The K ink operation screen shows that it has entered the acceptable range, and if the density is increased by 0.15, the color difference can be reduced from 2.84 to 1.08.

Clicking on the gray color patch, the red warning on the screen shows that L is less by 4.46, but the gray difference is okay, only 1.35. The operation instructions are C-3, M-5, Y-4. By following the instructions, the gray balance can be improved.

The above content explains that with the help of a simple mobile app, it is possible to quickly determine the quality of printing and guide towards better operational directions.

The scoring function of the first layer can be used as an acceptance criterion for print buyers or an internal control standard for the quality control department. It can also be used for self-control of the printing department.

This layer’s function is also used to put standardized pressure on the production unit and encourage it to produce standardized products.

The second layer provides clear guidance to the printer on how to operate the machine into a better position. Production units can also use this data to ensure their production quality, rather than blindly catering to customers’ unreasonable preferences and requirements.

With this working model, it is easier and faster to implement the concept of printing standardization in this industry. As the threshold for building and operating the system is lowered, more people in the industry can enter the digital domain.

The basic working model has been established and is feasible in practice. In terms of concept, the gray balance operation (relative to absolute color value operation for solid color) is a relative operation concept (gray balance target value is relative to the paper). This relative operation context does not require high absolute accuracy from the instrument but only requires instrument stability.

The market demand for quality varies, and the pursuit of high quality is always a direction worth striving for. However, finding a work method that can quickly and effectively meet the quality demands of 80% of the market is also a direction worth striving for.

The basic working model has already been completed, and what is expected in the future is:

• More accurate and affordable instruments.

• Instruments with scanning capabilities (strip reading) to collect more data faster.

• There are still many possible applications of the data, such as optimizing instrument values through machine learning, predicting customer color and quality preferences through data AI, and monitoring and managing the entire printing system through databases.

For me, there are still many things to do, and I don’t know when I will be able to make a difference. Li Hongzhang said that one generation should do one generation’s work, but I say that one type of person should do one type of work. I will just do what I need to do!