MANIFESTACIJA EFEKTA SIMULTANOG KONTRASTA U OVISNOSTI O PROMJENI TISKOVNE PODLOGE

Krunoslav Hajdek, Ivan Budimir

Sažetak

U radu su prezentirani rezultati usporedbe utjecaja efekta akromatskog simultanog kontrasta na dvije različite tiskovne podloge. Prezentirani uzorci sadrže 10 različitih varijacija svjetline pozadine i imaju raspon vrijednosti od 10 -100 % RTV u koracima povećanja od 10% RTV-i (vanjski kvadrat) koji okružuje primarni stimulus konstantne svjetline 50% RTV-a na specifično konstruiranom dizajnu. U psihofizikalnom vizualnom eksperimentu koji je proveden na 10 ispitanika i to za svaki pojedini uzorak, utvrđen je intenzitet i smjer odstupanja pojavnosti svjetline u CIEDE00 sustavu. Korištena je verificirana tehnika simultanog binokularnog usuglašavanja. Rezultati statističke analize daju smjer i intenzitet efekta na premazanoj i nepremazanoj podlozi. Provedeni Studentov t-test usporedbe aritmetičkih sredina odstupanja u svjetlini jasno pokazuje da se efekt simultanog kontrasta jače manifestira na nepremazanoj podlozi na uzorcima s 10%,20%,40%, 50%, 90% i 100% RTV-a pozadine (p<0.05). Na uzorcima s 30%, 60%, 70% i 80% RTV-a pozadine ne postoje statistički značajne razlike među uzorcima (p<0.05).

Ključne riječi: simultani kontrast, akromatska reprodukcija, premazana i nepremazana podloga, Studentov t-test

THE MANIFESTATION OF THE SIMULTANEOUS CONTRAST EFFECT DEPENDING ON THE CHANGE OF PRINTING SUBSTRATE

Krunoslav Hajdek, Ivan Budimir

Abstract

The paper presents the results of the comparison of the achromatic simultaneous contrast effect on two different printing substrates. The presented samples contain 10 different variations of background lightness and have a value range from 10 to 100% RTV in increments of 10% RTV (external square) that surrounds the primary stimulus of the constant lightness of 50% RTV on a specifically constructed design. In the psychophysical visual experiment conducted on ten subjects for each sample, the intensity and direction of the variation of the occurrence of lightness in the CIEDE00 system has been determined. The verified technique of simultaneous binocular harmonization was used. The results of the statistical analysis give the direction and intensity of the effect on a coated and uncoated substrate. The conducted Student’s t-test of the comparison of arithmetic means of lightness variations clearly shows that the effect of simultaneous contrast is more strongly manifested on an uncoated substrate on samples with 10%,20%,40%, 50%, 90% and 100% of the RTV of the background (p<0.05). On samples with 30%, 60%, 70% and 80% of the RTV of the background, there are no statistically significant differences between the samples (p<0.05).

Keywords: achromatic reproduction, coated and uncoated substrate, simultaneous contrast, Student’s t-test