Color conspicuity at the Purkinje shift

We used the samples prepared by letting the background stimulus color change so that the size of contrast will differ from the test stimulus color in various ways, studied the relation between contrast and advancing color in the three directions of value, chroma, and hue, also let the illuminance level change, and examined the influence of Purkinje shift. As a result, we found in the value contrast and chroma contrast that in any hue, as the contrast with the background becomes higher, the stimulus looks closer, and we could not observe any influence of Purkinje shift. However, in an experiment in which only the hue is different at the same values of the value and chroma between the test stimuli, we could observe the influence of Purkinje shift in that, when only the background stimuli is N1, a blue color looked most advancing in the mesopic vision, whereas a red color looked most advancing and the blue color did not look advancing in the photopic vision.