Impacts of Package Colour on Preferred Image Colour, Contrast and Sharpness: Taking Package Design of Orange Juice as an Example

Due to the effects of colour harmony, preference of a foreground image varies with the background colour. This is an important issue in graphic design of packages as foreground images and background colours are two salient features. Graphic design of an orange juice package was examined as an example in present study to find out the relationship between the background colour of the package (i.e. package colour) and the foreground image in terms of colour, contrast and sharpness. A psychophysical experiment was conducted using 30 package colours as the variables, with which the observer's task was to achieve a satisfactory package appearance by adjusting colour, contrast and sharpness of an orange image as the foreground. Considering observers' Areas of Interests (AOI) while adjusting the image of orange, the results showed that to achieve a satisfactory packaging design, the higher the values of lightness/chroma for a package colour, the higher values of lightness/chroma were required for the orange image. In the case of image contrast, two distinct trends were found for the relationship between image contrast and the ΔEN0 of package colour (i.e. CIELAB colour difference between the package colour and black). The first trend can be illustrated by a positive accelerated increasing function in the case of reddish-yellow package colours and the second trend was a negative accelerated increasing function for non-reddish-yellow package colours. With regard to sharpness, package colours were found to have little impact on sharpness of the orange image.