
Discussion on Control Methods for Spot Color Dot Enlargement in Packaging and Printing
Release Time: 2026-01-04 00:00:00.000
With the widespread adoption of spot-color halftone images in packaging and printing, accurately reproducing the image gradations and details that meet customer requirements has become crucial. This article starts with two core approaches—control of dot gain and color difference control—and analyzes their technical principles, application scenarios, and optimization directions.
Network Expansion Rate Control
By controlling the degree to which the halftone dot area is increased in spot-color printing, ensure that the tonal range of the printed material meets the standards. Common methods include:
1. Mary Davis Formula
This is a traditional method for calculating dot gain. It is commonly used in conventional four-color printing, where the change in dot area is measured to assess tone matching. Some printing plants also routinely adopt this method when controlling the tones of spot colors.
2. SCTV Method
Spot Color Tone Value, the latest spot-color tonal technology based on spectral curves, enables more precise matching of visual hierarchy.
Advantage
The dot-area data for SCTV is smaller, the tonal gradations are nearly equidistant, the transition in the shadow tones is smoother, and the 50% tone is closer to the midpoint between the paper color and the solid ink color.

Application
Quick setup and measurement using the eXact instrument, combined with dot gain data to digitally represent print tonal ranges.


Color Difference Control (Undertone 50% Color Difference)
The color difference between the 50% halftone of the spot color and the printed sample must be evaluated comprehensively by combining the following four methods:

Key points
When establishing color standards, it is necessary to include tone area values ranging from 25% to 75% (with at least 50%), in order to support multi-method data matching.

A single method has limitations; it is recommended to combine dot gain control with color difference control to improve midtone accuracy.

Same-tone contrast

Best Match Comparison

Comparison of identical densities

Same Brightness Comparison
Summary
In packaging printing, controlling midtones in spot colors requires balancing dot gain and color difference analysis.
1. Network Expansion Rate Control (Such as the SCTV method) can optimize tonal gradation and is particularly well-suited for visually matching dark tones and midtones.
2. Color difference control By conducting multi-dimensional comparisons (such as ΔE, density, and brightness), we can specifically address issues like ink formulations and ink film thickness.
3, Comprehensive Application These two methods, combined with the establishment of standard data that includes multi-level tonal values, are key to achieving accurate color reproduction.
Some of the pictures and texts in this site are collected and collated from the network for learning and exchange only. The copyright belongs to the original author. If you have violated your rights, please contact us to delete them in time.
More News
Kaiyin Technology - Awarded "Specialized and New Enterprise"
Kaiyin Technology, with its professional R&D and service teams, sound management system, and excellent innovation mechanism, successfully passed the enterprise self-assessment, Shenzhen municipal preliminary examination, and national ministry review procedures, ultimately winning multiple honorary titles including "Specialized and New Enterprise," "High-tech Enterprise," and "Innovative Small and Medium-sized Enterprise." The acquisition of these honors is a high recognition of Kaiyin Technology's innovation capabilities, technological R&D strength, and industry specialization, and further affirmation of the company's innovative development achievements. It marks another significant step forward for Kaiyin Technology in technological innovation and development in its specialized field.
MeasureColor and eXact AutoScan help you achieve exceptional print quality.
Achieving stable print quality hinges on your ability to control dot gain—a critical yet often overlooked variable. Dot gain significantly impacts color accuracy, image sharpness, and overall visual performance, particularly in packaging printing and workflows involving expanded color gamuts. With MeasureColor, printers can access advanced tools that enable them to effortlessly monitor, manage, and optimize dot gain in real time—eliminating the need for subjective guesswork.
On the journey toward higher precision, greater efficiency, and more sustainable development in the printing industry, the plate-making stage has always served as a crucial link—connecting the past with the future. As numerous printing companies choose among the dazzling array of CTP (Computer-to-Plate) equipment available, one well-known name—Kodak—often finds itself at the center of attention with its CTP solutions.
In manufacturing, even the slightest difference in color can often be the dividing line between high-quality and substandard products. Whether it’s apparel, building materials, cosmetics, or durable consumer goods, consistently accurate colors are not only a pursuit of product aesthetics—they also serve as the cornerstone of brand commitment and customer trust. Achieving this goal is inseparable from powerful color measurement tools—high-performance spectrophotometers.
Service Hotline:
180 8888 0185
Address:
605, Building B1, Funian Plaza, No. 3, Shihua Road, Futian District, Shenzhen, Guangdong
Tel:
Fax:
Email:
Copyright ©Shenzhen Kaiyin Technology Co., Ltd 粤ICP备16126578号 SEO
Website support:300.cn ShenZhen
Mobile: 180 8888 0185
Tel: +86 755 8280 8180
Address: 305A, Floor 3, Building B1, Funian Plaza, No. 3, Shihua Road, Futian District, Shenzhen, Guangdong
Email: service@kngcolor.com
We will give you feedback in time
