Browse > Article
http://dx.doi.org/10.5657/kfas.2009.42.2.171

Assessment of Seawater Color by Digital Photographic Imaging  

Choi, Sok-Jin (Machinery & Metals and Construction Examinations Bureau, Korean Intellectual Property Office)
Arakawa, Hisayuki (Department of Ocean Sciences, Tokyo University of Marine Science and Technology)
Publication Information
Korean Journal of Fisheries and Aquatic Sciences / v.42, no.2, 2009 , pp. 171-178 More about this Journal
Abstract
The purpose of this study was the development of a digital water color measurement system using a CCD optical device. Photographs of the standard medium of Forel and Ule water color scales in the laboratory, and one of sea surface above a Secchi disc (Z=SD/2) immersed in seawater were taken. The colors of these pictures were estimated with the value of CIE $L^*a^*b^*$. Water color assessment was conducted with a digital photo-image. In the case of the Forel scale (No. 1-11), the $b^*$ value was so high that the water color number was large. In the Ule scale (No.11-21), the $a^*$ value became high, which is why the number on the water color scale was large. The color of these pictures showed that the $a^*$ value in the Forel scale and the $b^*$ value in the Ule scale increase with the increase of the F value. The $a^*$ value of seawater color was always lower than the one on the Forel and Ule water color scales. This indicates that the color of the scales differs from actual seawater color. It was concluded that water color number can more effectively be assessed by estimating the ${\Delta}Eab^*$ color difference between the water scales and actual seawater color.
Keywords
Digital image; Water color; Forel scale; Ule scale; CIE Lab;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Baba, G., H. Sobagaki, K. Okubo and M. Fukuda. 2001. Measure the color, method of color comparison and standard object. In: Handbook of Color Science. The Color Science Association of Japan, ed. Tokyo University Press, Tokyo, Japan, 179-256
2 The Oceanographic Society of Japan. 1979. The ocean environmental research method. Kouseisha, Tokyo, Japan, 126-128
3 Ohta, N. 1993. Color Engineering. Tokyo denki University Press, Tokyo, Japan, 115-170
4 Kuroki, M. 1982. The ocean environmental measurement. Kouseisha, Tokyo, Japan, 58-63
5 Komatsuhara, H., M. Fukuda, G. Baba, K. Suzuki and Y. Uchida. 2001. Colour difference. In: Handbook of Color Science. The Color Science Association of Japan, ed. Tokyo University Press, Tokyo, Japan, 258-303
6 Suginohara, S. 1969. The color of the sea in the sound between Denmark and Sweden with a new colorimeter. Rep. Inst. Fisk Oceanography Copenhagen, 8, 1-8
7 Wood, P. and A. Cunningham. 2001. Ship-borne measurements of ocean colour: Development of a CCD-based reflectance radiometer and trials on a longtitudinal transect of the atlantic ocean. Int. J. Remote Sensing, 22, 99-111   DOI   ScienceOn
8 Zhao, F. and T. Nakajima. 1997. Simultaneous determination of water-leaving reflectance and aerosol optical thickness from coastal zone color scanner measurements. Applied Optics, 36, 6949-6956   DOI
9 Fukuda, M. and R. Tsuda. 1980. consideration of problems in transparency measurements. La mer, 18, 46-60
10 Okami, N. and M. Kishino. 1975. On the relation between color of Forel and Ule's Standard solution and color of sea. La mer, 13, 171-178
11 Smith, R.C., J.E. Tyler and C.R. Goldman. 1973. Optical properties and color of Lake Taho and Creater Lake. Limnol. Oceanography, 18, 189-199   DOI   ScienceOn
12 Japan Meteorological Agency. 1970. The guide of ocean observation. The oceanographic society of Japan, Tokyo, Japan, 85-89