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In this study, using the grapes as the experimental materials, it was examined a new technique for getting the information on the tree growth using a digital camera instead of the human eyes. First, we established the method that the true surface color of the fruit cluster was measured with the standard RGB color chart and the color transformation matrix in the outdoor conditions. As a result, the influence of the light conditions in the field was eliminated, and it became possible to evaluate their skin color. Furthermore, it became clear that using this method could make the non-destructive and continuous verification of the coloring behavior of the fruit cluster. Then, we studied the nutrient conditions by the image analysis of the grape leaf. Because the shape and the color belong to the sensuous information, it is difficult to analyze these information and to determinate a standard value. In this experiment, the outline data of the leaf was analyzed in the polar coordinate so that the character of the shape was quantitatively classified. In conclusion, it was shown that the possibility of quantifying the important factors in the cultivation, which farmers usually acquired visually from grape tree.