• Title/Summary/Keyword: Colour difference

Search Result 85, Processing Time 0.02 seconds

Investigating the Colour Difference of Old and New Blue Japanese Glass Pigments for Artistic Use

  • Chua, Lynn;Quan, Seah Zi;Yan, Gao;Yoo, Woo Sik
    • Journal of Conservation Science
    • /
    • v.38 no.1
    • /
    • pp.1-13
    • /
    • 2022
  • Colour consistency is an important consideration when selecting pigments used on works of art. In this study, we analyse the colour difference between two sets of synthetic blue glass pigments acquired at least 8 years apart from the same manufacturer in Japan. The old pigment set (unused, dry powder with four different grain sizes) appears faded compared to the new set. These pigments are made available for artistic use, commonly in Nihonga or Japanese paintings. Raman spectroscopy and SEM-EDS results characterize these pigments as cobalt aluminate spinels dissolved in leaded glaze, a special class of complex coloured inorganic pigments that is not well-understood in the field of conservation. Colour difference between the old and new pigments with four different grain sizes were quantified by analysing photomicrographs with image analysis software. Blue pigments with coarse and extremely fine grains showed significant colour change compared to pigments with medium and fine grain sizes. The high occurrence of crystallites in the finer grains give a final colour that is bluer and lighter. Possible causes for the colour difference including manufacturing methods and storage environment are discussed.

Colour Interpolation of Tongue Image in Digital Tongue Image System Blocking Out External Light (디지털 설진 시스템의 색상 보정)

  • Kim, Ji-Hye;Nam, Dong-Hyun
    • The Journal of the Society of Korean Medicine Diagnostics
    • /
    • v.16 no.1
    • /
    • pp.9-18
    • /
    • 2012
  • Objectives The aim of this study is to propose an optimized tongue colour interpolation method to achieve accurate tongue image rendering. Methods We selected 60 colour chips in the chips of DIC color guide selector, and then divided randomly the colour chips into two groups. The colour chips of a group (Gr I) were used for finding the optimized colour correction factor of error and those of the other group (Gr II) were used for verifying the correction factor. We measured colour value of the Gr I colour chips with spectrophotometer, and took the colour chips image with a digital tongue image system (DTIS). We adjusted colour correction factor of error to equal the chip colour from each method. Through that process, we obtained the optimized colour correction factor. To verify the correction factor, we measured colour value of the Gr II colour chips with a spectrophotometer, and took the colour chips image with the DTIS in the two types of colour interpolation mode (auto white balance mode and optimized colour correction factor mode). And then we calculated the CIE-$L^*ab$ colour difference (${\Delta}E$) between colour values measured with the spectrophotometer and those from images taken with the DTIS. Results In auto white balance mode, The mean ${\Delta}E$ between colour values measured with the spectrophotometer and those from images taken with the DTIS was 13.95. On the other hand, in optimized colour correction factor mode, The mean ${\Delta}E$ was 9.55. The correction rate was over 30%. Conclusions In case of interpolating colour of images taken with the DTIS, we suggest that procedure to search the optimized colour correction factor of error should be done first.

New Weighting Functions for the Modified CIELAB Colour-Difference Formulae (수정 CIELAB 색차식을 위한 새로운 색차 가중 함수)

  • Kim, Dong-Ho
    • Textile Coloration and Finishing
    • /
    • v.9 no.6
    • /
    • pp.51-57
    • /
    • 1997
  • The lightness, chroma and hue tolerances with respect to the standard colour position in the CIELAB space have been studied in detail using the various existing data sets and the set form this study. The lightness tolerance showed a clear dependency upon the metric lightness for medium to light colour, but in the case of dark colours there was a discrepancy between the data sets. Both the chroma and hue tolerances showed dependency upon both the chroma and hue-angle and not the single dependency upon the metric chroma, as assumed in the CIE94 formula. New weighting functions were derived from the above experimental evidence, and finally a new formula, LCD(Leeds Colour Difference) was proposed. The LCD formula is nearly as simple and flexible as CIE94 but smoothes the individual weighting functions, especially for lightness tolerances for light colours and chromaticity discrimination near the blue region.

  • PDF

Color Differences of Standard Samples according to Their Lightness Levels (명도 수준에 다른 목표 샘플의 색차)

  • Kim Jeong Ryeol;Lee Seung Jun;Kim Sam Soo
    • Textile Coloration and Finishing
    • /
    • v.17 no.2 s.81
    • /
    • pp.19-25
    • /
    • 2005
  • A colour-difference formulae would be based on a colour appearance model, but, So far, most colour-difference formulae in common use are based on empirical fits to data. Therefore, of the many proposed, none are completely satisfactory but advances have been made in recent years. A new color-difference data set has been produced with the aims of making a comparison of the advanced CIE Lab formulae as well as confirming the effect of color-difference. 416 low lightness pairs that have only lightness-difference were produced for evaluation of CIE Lab-based formulae on lightness-difference from glossy polyester fabric. The standard color-difference pair was prepared and used. It was neutral grey sample pair that has only lightness difference. The standard pair was used to investigate lightness tolerances. And grey-scale method used to evaluate visual assessment. CIE Lab coordinates of the samples were measured using a X-Rite 8200 spectrophotometer. Visual assessments were carried out using Gretag Macbeth The Judge II Light Booth. A study of color tolerances at low lightness was carried out and get avaliable some results.

Globular Cluster Systems of Early-type Galaxies in Low-density Environments

  • Cho, Jae-Il;Sharples, Ray
    • Bulletin of the Korean Space Science Society
    • /
    • 2010.04a
    • /
    • pp.34.4-34.4
    • /
    • 2010
  • We present the properties of globular cluster systems for 10 early-type galaxies in low density environments obtained using deep images from the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope (HST). Using the ACS Virgo Cluster Survey as a counterpart in high-density environments, we investigate the role of environment in determining the properties of their globular cluster systems. We detect a strong colour bimodality of globular cluster systems in half of our galaxy sample. It is found that there is a strong correlation between the colour and richness of globular cluster populations and their host galaxy luminosities: the less bright galaxies possess bluer and fewer globular clusters as also seen in rich cluster environments. However, the mean colour of globular clusters in our field sample are slightly bluer than those in cluster environments at a given galaxy luminosity, and the colour of the red population has a steeper slope with absolute luminosity. By employing the YEPS simple stellar population model, the colour offset corresponds to metallicity difference of $\Delta$[F e/H ] ~ 0.15 - 1.20 or an age difference of $\Delta$age ~ 2 Gyr on average, implying that GCs in field galaxies appear to be either less metal-rich or younger than those in cluster galaxies. Although we have found that galaxy environment has a subtle effect on the formation and metal enrichment of GC systems, host galaxy mass is the primary factor that determines the stellar populations of GCs and the galaxy itself.

  • PDF

Sputter Etching and Chlorination of Wool Fabric (양모직물의 Sputter Etching 및 염소처리)

  • Hwang, Back-Soon;Lee, Jae-Ho;Park, Jung-Whan;Kim, Duk-Ly
    • Fashion & Textile Research Journal
    • /
    • v.3 no.4
    • /
    • pp.344-350
    • /
    • 2001
  • Wool fabrics were treated with dichloro isocyanuric acid (DCCA) and dyed with acid dyes (C.I. Acid Red 18), and then, they were treated by sputter etching. Wool fabrics had been sputtered with aluminium under various conditions such as sputter etching time and discharge power in the presence of argon gas. We compared mechanical properties, colour difference and fastness properties of these samples one another: Mechanical properties and colour difference of sputtered wool fabrics changed by sputter etching time, discharge power and DCCA concentration. Light fastness showed a rising tendency but rubbing fastness showed a downward tendency when sputter etching time was 7 minutes.

  • PDF

A Study on the Characteristics of Colour Perception According to Light and Dark Mode in the Digital Media Environment (디지털 미디어 환경에서 사용자 환경 모드에 따른 색채 인지 특성 연구)

  • Ji-Young Hong
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.23 no.3
    • /
    • pp.65-70
    • /
    • 2023
  • In recent years, the digital media environment has begun to diversify, with a greater focus being placed on user-centric design. With the development of digital technology, the digital media environment has formed a vast network of information, which supports interactive communication between people, creating a need for user-centric research. Mobile displays, as a representation of the digital media environment, have the advantage of mobility through the use of thin screen displays and low-performance image sensors, which allow for miniaturization and power saving. However, this results in reduced colour accuracy compared to large displays. This study investigates users' colour perception when using dark and light mode mobile displays. Colour perception was measured using a psycho-physical experiment, which controls each colour attribute based on the 12 colours of KS. The results were analysed to determine whether there is a difference in colour perception between dark mode and light mode, and if the difference was statistically significant. Future research directions based on the results are then discussed.

An Experimental Study on the Spatial Effects of Colours - with relevance to colours of ceilings , walls and floors in living rooms - (실내색채의 공간효과에 관한 실험연구 - 거실의 천장 , 벽 , 바닥 색채를 중심으로 -)

  • 조원덕
    • Journal of the Korean housing association
    • /
    • v.3 no.2
    • /
    • pp.13-19
    • /
    • 1992
  • The purpose of this study is to grasp spatial effects of colours in interior design. The visual feeling in the 1/10 living room scale models that are different in the colour combination of ceilings, walls and floors is judged using a semantic scale of the fifteen adjectives. The major findings are as follows; 1) As a result of factor analysis, three dimensions, "evaluation", "activity" and "warmness" are extracted. Dimension 1, "evaluation", is most greatly affected by the chroma and hue of the room colour, dimension 2, "activity", by the hue and value, by the difference in hue and value of ceilings, walls and floors, dimensions 3, "warmness", by mainly the hue of the rooms. 2) Concerning the spatial effects of colour, the subjects felt higher vlaue with relevance to the hue of GY, Y, low chroma and high value. The room colours other than walls is felt more comfortable in similar colour, especially hue and value.re comfortable in similar colour, especially hue and value.

  • PDF

Comparison between Colour Intensity of Tongue Body and That of Tongue Coat under the Ultraviolet Light in RGB system of Peeling Tongue Coat Image (RGB 컬러모델에서 자외선 조명하 박락태(剝落苔)의 설태와 설질 사이의 색 강도 차이에 관한 연구)

  • Nam, Dong-Hyun;Kim, Ji-Hye;Lee, Woo-Beom;Lee, Sang-Suk;Hong, You-Sik
    • The Journal of the Society of Korean Medicine Diagnostics
    • /
    • v.15 no.2
    • /
    • pp.149-158
    • /
    • 2011
  • Objectives: The objective of this study is to compare the colour intensity of tongue body and that of tongue coat under the visible light and the ultraviolet light. Methods: We selected 7 subjects with completely or partially peeled tongue coat among the recruited 94 adults for the experiment. We took each tongue picture under the visible light and the ultraviolet light (315-400 nm) and then extracted sample images from the tongue body and tongue coat regions. Mean, median and mode of colour intensity from the sample images were calculated in 256 RGB system. Results: The green and the blue colour intensities of the tongue coats were significantly higher than those of the tongue bodies under the visible light. In all channels, the red, green and blue, the colour intensities of the tongue coats were significantly higher than those of the tongue bodies under the ultraviolet light. The colour differences between tongue coats and tongue bodies under the ultraviolet light were significantly higher than the colour differences under the visible light. Especially the colour difference under the ultraviolet light was highest in the green channel. Conclusions: We suggested that green colour image of the RGB system taken under the ultraviolet light could be used for more easy separating tongue coat region from tongue body.

Sensory Image and Preference of the Color Green Shown in Modern Fashion - With Regard to Busan, Ulsan and Gyungnam Area - (현대패션에 나타난 그린 컬러의 감성이미지 및 선호도 - 부산, 울산, 경남 지역을 중심으로 -)

  • Park, Younghee
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.17 no.1
    • /
    • pp.131-140
    • /
    • 2015
  • After drawing the sensory images from the color green, the difference of sensory images and the difference of the color green according to demographic characteristics and which factors affect the preference have been analysed. The thirty six-photos of 2013 women fashion show on the STYLE.COM were used for the stimuli of green colour fashion for the questionnaire. The people surveyed were adults in their 20s to 50s. The 123 copies of the questionnaire were used for the statistical analysis of this study. Factor analysis, Cronbach's ${\alpha}$ test, t-test, ANOVA, Duncan test and Regression analysis test were carried out by SPSS 19 for the statistical analysis of collected data. The results were as follows. The sensory images of green fashion were drawn in six types. The sensory images of green fashion according to demographic characteristics showed a significant difference depending on martial status, age, monthly income and occupation. The preference of green colour fashion according to demographic characteristics showed a significant difference depending on sex, age, monthly income, occupation. The variables affecting the preference of green fashion were identified as four types, and the most affecting variable to the preference was the favorable and familiar factor. These research results will become available on selecting the target customer and making the marketing differentiation strategy when planning fashion products.

  • PDF