A Survey of digital and offset print quality issues

Using an Internet-based industry survey, the differences and similarities of offset and digital print demerits within the print industry are examined. Running parallel to this examination is a look at the extent to which demerit-based quality assurance procedures exist within the printing industry. The survey findings indicate that offset and digital printing processes share common color-related print demerits. What differentiates offset print demerits from digital print demerits can be attributed to two factors: (1) technology differences and (2) printing standards. Offset printing, given the multitude of material choices, produces more frequent print demerits, relating to non-conforming materials. Digital print demerits more likely result from technical constraints such as addressability and resolution. The other factor associated is a lack of printing standards for digital printers. While both processes show a high frequency of color-related problems, offset print providers have more tools and standards available for addressing these problems. Digital print providers, on the other hand, have few color standards or tools for solving similar problems. When examining procedures for defect prevention, the general lack of digital printing standards makes the use of formal quality assurance procedures difficult. Offset print providers are more likely to have formal quality assurance procedures for dealing with frequent and severe print demerits and formal procedures for how customer quality requirements are communicated

INCITS W1.1 Standards for Perceptual Evaluation of Text and Line Quality

INCITS W1.1 is a project chartered to develop an appearance-based image quality standard. This paper summarizes the work to date of the W1.1 Text and Line Quality ad hoc team, and describes the progress made in developing a Text Quality test pattern and an analysis procedure based on experience with previous perceptual rating experiments

Recent Progress in the Development of INCITS W1.1, Appearance-Based Image Quality Standards for Printers

In September 2000, INCITS W1 (the U.S. representative of ISO/IEC JTC1/SC28, the standardization committee for office equipment) was chartered to develop an appearance-based image quality standard.(J),(2) The resulting W1.1 project is based on a proposal(4) that perceived image quality can be described by a small set of broad-based attributes. There are currently five ad hoc teams, each working towards the development of standards for evaluation of perceptual image quality of color printers for one or more of these image quality attributes. This paper summarizes the work in progress

Tent-pole spatial defect pooling for prediction of subjective quality assessment of streaks and bands in color printing

Abstract. An algorithm is described for measuring the subjective, visual impact of 1-D defects (streaks and bands

Effects of Ink, Substrate, and Target Line Width on the Quality of Lines Printed Using a DMP 3000 Inkjet Printer

This thesis is concerned with the image quality analysis of inkjet lines printed on substrates. ISO 24790 compliant lines are designed and printed on a substrate with a drop-on-demand inkjet printer. This study analyzes three print quality attributes of line: width, blurriness, and raggedness. The research used cyan, magnetic and standard inks to print the same design on various substrates having differences in gloss and texture. The chosen inks were measured using a rheometer to determine a viscosity range. The effects of substrate structural parameters, such as texture, finishing, weight, and ink type on line quality, are discussed. The printed lines were measured using a charged coupled device camera. The print attributes were measured, and statistical analysis was conducted. Based on this analysis, it was observed that substrate has significant effect on all the response variables. The substrate which produced best result is luster for raggedness and line width conformity and matte for blurriness. Ink has significant effect on the line width conformity and raggedness whereas there is no significant effect of inks on blurriness. There is no effect of increase in the line width on any of the response variables. A design of experiment methodology was successfully implemented to determine the effect of surface properties of the substrate and the effect of ink properties on print quality

The Effects of Multi-channel Visible Spectrum Imaging on Perceived Spatial Image Quality and Color Reproduction Accuracy

Two paired-comparison psychophysical experiments were performed. The stimuli consisted of six image types resultingfrom several multispectral image-capture and reconstruction techniques. A seventh image type, color-managed images from a high-end consumer camera, was also included in thefirst experiment to compare the accuracy of commercial RGB imaging. The images were evaluated under simulated daylight (6800K) and incandescent (2700K) illumination. The first experiment evaluated color reproduction accuracy. Under simulated daylight, the subjects judged all of the images to have the same color accuracy, except the consumer camera image which was significantly worse. Under incandescent illumination, all the images, including the consumer camera, had equivalent performance. The second experiment evaluated image quality. The results of this experiment were highly target dependent. A subsequent image registration experiment showed that the results of the image quality experiment were affected by image registration to some degree. An analysis of the color reproduction accuracy and image quality experiments combined showed that the consumer camera image type was preferred the least over all. The most preferred image types were the thirty-one-channel image type and both six-channel image types created using RGB filters along with a Wratten filter, with eigenvector analysis and pseudo-inverse transformations

Handbook of Optical and Laser Scanning

From its initial publication titled Laser Beam Scanning in 1985 to Handbook of Optical and Laser Scanning, now in its second edition, this reference has kept professionals and students at the forefront of optical scanning technology. Carefully and meticulously updated in each iteration, the book continues to be the most comprehensive scanning resource on the market. It examines the breadth and depth of subtopics in the field from a variety of perspectives. The Second Edition covers: Technologies such as piezoelectric devices Applications of laser scanning such as Ladar (laser radar) Underwater scanning and laser scanning in CTP As laser costs come down, and power and availability increase, the potential applications for laser scanning continue to increase. Bringing together the knowledge and experience of 26 authors from England, Japan and the United States, the book provides an excellent resource for understanding the principles of laser scanning. It illustrates the significance of scanning in society today and would help the user get started in developing system concepts using scanning. It can be used as an introduction to the field and as a reference for persons involved in any aspect of optical and laser beam scanning

Print uniformity model for digital prints

Površinska uniformnost je jedan od ključnih parametara za analizu kvaliteta otisaka. Osnovni cilj istraživanja je definisanje modela za kvantifikaciju površinske uniformnosti digitalno štampanih otisaka. U nizu sprovedenih eksperimenata procenjen je uticaj ulaznog uređaja za digitalizaciju otisaka i uticaj varijabilnih podešavanja prilikom digitalizacije. U disertaciji su ispitane četiri metode za merenje površinske uniformnosti koje su najčešće korišćene u dosadašnjoj literaturi – GLCM, ISO 13660, Integralna i M-Score metoda. Na osnovu dobijenih rezultata i zaključaka istraživanja moguće je predložiti razvoj industrijski primenljivog rešenja za merenje površinske uniformnosti digitalno štampanih otisaka.Print uniformity is one of the key parameters for the analysis of print quality.The basic aim of the research is to define a model for the quantification of print uniformity of digitally printed samples. In the series of carried out experiments, the influence of the input device for digitalisation of prints and the influence of variable settings during digitization was evaluated. The dissertation examined four methods for measuring the surface uniformity most commonly used in the previous literature - GLCM, ISO 13660, Integral and M-Score method. On the basis of the obtained results and conclusions of the research, it is possible to propose the development of an industrially applicable solution for measuring the surface uniformity of digitally printed prints