Five-point evaluation method
1. The color difference of digital printing products can usually be divided into the following categories:
● color difference of original manuscript: color reproduction of original manuscript is the ultimate goal of digital printing products. The highest standard of subjective evaluation is to make digital printing and original manuscript indistinguishable from each other.
● the same batch of color difference: refers to the same batch of products in the same color region of the same position, different printing between the color difference.
● Color difference: refers to the same product in different batches of color difference. If there is no color difference in each batch, when these products are put together, the contrast will be unusually obvious. The customers will feel that the products are old and new, and the external color difference will affect the trust in the quality of the products. In this way, the customers will be dissatisfied with the manufacturers and the subsequent cooperation will be affected.

2.Color tolerance refers to the difference between the original and sample acceptable to the customer.
As the customer and the manufacturer, we all hope to be able to control the color difference between the product and the original manuscript to 0, but due to the actual production and the limitations of all aspects, it is impossible to completely eliminate the color difference. Therefore, in order to control the chromatic aberration to the minimum, the chromatic aberration can only be reduced to the minimum by strengthening the control of each link. Keep it within the prescribed limits.

3.Whether in the process of printing or in the quality inspection after the finished product, the printing operator and the quality inspection personnel should make an objective evaluation on the color quality of the printing product by virtue of their own experience and feelings to show the sense of authenticity of the product. Digital printing can be said to be a kind of reproduction, from the prepress processing to the whole printing process, the original is the basis for the production of digital printing, reproduction of the color of the original is the purpose of digital printing reproduction.

4.In the absence of the most contrasting original manuscripts, the color quality of digital printing is related to the sense of authenticity, that is to say, the product should conform to the memory color of most people. When people see a product, they will present a kind of memory color in their mind. If the main color in digital printing is quite different from the real color, the product cannot be regarded as a high-quality finished product.

5.Objective evaluation. The quality of digital printing can be calculated from the subjective evaluation results by statistical means, and then converted into the corresponding physical quantities, which can be used as the objective evaluation criteria. This is actually relatively objective, will not appear the influence of human factors, because it is standardized by the unified standard of the fair evaluation, will also meet the standards of the majority of people will be accepted by more people