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Skin face detection in photo imaging, is an important component of systems for detecting similarities in visual perception, tracing faces through illumination and metamerism. This paper presents an evaluation of the skin perception under standardized conditions of varied light sources: cool-white fluorescent “store light”, 6500K fluorescent “daylight”, and incandescent “home light”, Led light 6500 K, 2700K, 4000K CCT. In cases where the discrepancy is large, the resulting index of metamerism can be misleading. A small index of metamerism and a large change of color under illuminant metamerism has a different interpretation than what is perceived. This has been demonstrated through small colour variations in print through CMYK colors. The implication is that particular indices of metameric should only account for a limited range under different light conditions. The method used in this paper is based on visual perception, which aim to work with a wide variety of individuals, under varying lighting conditions under the influence of standard daylight, but in this case we also used the Led light 6500K correlated colour temperature, and variations of skin color tones, comparing the illuminant metamerism of visual perception based on different reflectance power distributions (SPDs).

Appropriate labeling and flexible packaging plays an important role on the today`s demands. There is diverse possibilities especially related to polymeric materials. Flexible packaging means to consider options such as OPP (Oriented Polypropylene), PVC (Polyvinyl Chloride), OPS (Oriented Polystyrene), PET (Polyethylene Terephthalate) or all kind of self-adhensive paper and foil types. Special highlight are the "Shrink Sleeve" labels that meet the most demanding market challenges. Its capabilities are beneficial. Laminated packaging materials are functional. Both constitute protection and packaging capacity. Coefficient of friction is the value that serves to meet the standard of how the flexible packaging material will glide and move on the packaging machine. This research is focused on the optimum quality of the packaging production process to meet all the preconditions for implementation of the semifinished product packaging and to avoid difficulties and possible stoppages on the packaging machine itself.

Raznovrsne tehnologije tiskarskih procesa uzrokuju različita odstupanja u kvaliteti otisnutog grafičkog proizvoda. Etikete kao grafički proizvodi osjetljive su na takve promjene, budući najčešće predstavljaju prvi kontakt između kupca i proizvoda na koji je etiketa aplicirana. Ovo istraživanje usmjereno je na otiske kojima dominiraju tamnije boje, otisnute tehnikom ofsetnog tiska. Cilj ovih istraživanja je na osnovu spektrofotometrijskih mjerenja i vizualne ocjene kvalitete tiska, konstruirati MacAdamsove elipsoide i ustanoviti je li moguće MacAdamsovim elipsodima ustanoviti kvalitetu tiska u području tamnih boja. Nakon provedenih istraživanja, ustanovljeno je da elipsoidi pokrivaju različita područja unutar CIE L*a*b* sustava. Osim navedenog ustanovljeno je da je vizualnom procjenom moguće percipirati male promjene u tamnim bojama, ali ne u svim vrijednostima linearno. Korelacijom navedenih rezultata, zaključeno je da je prilikom ustanovljavanja kvalitete tiska tamnih boja moguće koristiti MacAdamsove elipsoide., Various technologies of printing processes induce various deviations in the quality of the printed graphic product. Labels as graphic products are sensitive to such changes, since they represent the first contact between the consumer and the product the label is applied on. This research is oriented towards imprints dominated by dark colours, printed using the offset printing technique. Goal of this research is to, based on the spectrophotometric measuring and visual evaluation of the printing quality, construct the MacAdams ellipsoids and establish whether it is possible to establish the printing quality in the area of dark colours using MacAdams ellipsoids. After conducted research it was established that the ellipsoids cover various areas within CIE L*a*b* system. By correlating the stated results, it was concluded that while establishing the printing quality of the dark colour it is possible to use MacAdams ellipsoids.

Nowadays, flexographic printing process is the most cost-effective printing technique. Due to its capacity to produce very good print quality it is predominantly used for labelling and packaging applications. Additionally, flexography has become a very strong competition to the gravure printing process in performing more demanding printing tasks. In order to improve reproduction quality obtained by flexographic printing technique, some modifications in producing printing plates have been developed in the recent years. In this paper, two new technologies, DigiCap and SquareSpot, are presented. The aim of the research was to analyse and define the quality of reproduction obtained with DigiCap and SquareSpot technologies in the production of printing plates. The definition of the overall reproduction quality was determined using objective and subjective analysis. Three image quality attributes were observed: line reproduction quality, circularity of dots and dot gain in objective analysis.

Visokopigmentirane boje imaju mogućnost s tanjim slojem boje prekriti rasterske elemente pri čemu je intezitet njihova obojenja veći u odnosu na klasične boje. Upotrebom takvih boja otisci dosegnu točku gdje se prirast rastertonske vrijednosti i prostor reprodukcije mijenja, a koja je usko povezana s granicama kvalitete otiska. Ovo je također izravno povezano sa standardizacijom tiska i ponovljivosti tiskarskog procesa. Upravo zbog toga naše istraživanje smo usmjerili na povećanje kvalitete reprodukcije upotrebom visokopigmetiranih boja. Otiskivanje je provedeno na dvije vrste papira koji se najčešće koriste u tehnici ofsetnog tiska. U ovome radu, kvaliteta reprodukcije vizualno je ispitivana s promjenjivim vrijednostima gustoće obojenja, prirastom rastertonskih vrijednosti i gamutu boja. Ovaj rad sadrži također i nove, preporučljive vrijednosti prirasta rastertonske vrijednosti i prostora reprodukcije boja kada se otiskivanje obavlja korištenjem visokopigmentiranih boja., Highly pigmented inks have the ability to cover screen elements with a thinner layer of ink applied whereby the intensity of their inking is higher compared to the classical inks. When using such inks, the printing reaches the point where the ink dot gain and the space of reproduction changes, which is closely related to the limits of the print quality. This is also directly related to the standardization of the print and the repeatability of the process. For this reason our research is focused on increasing the reproduction quality by using highly pigmented inks. The printing was carried out on two types of paper that were most commonly used in offset printing technology. In this paper, the reproduction quality was visually determined at changeable values of the inking densities, dot gain and gamut of colour. This paper also contains the new, recommended values of dot gain and gamut for printing processes using highly pigmented inks.