Establishment of whiteness (W) – lightness (L*) relationship
Use a gray scale of 16 steps.
Measure L* by an instrument.
Obtain the amounts of whiteness and blackness for the gray scale.
Subjects: 30 persons with normal color vision.
Each person repeats 10 times of the measuremrnt.
A proper way of presenting the stimulus should be employed (Yum thinks about this).
Read a paper, Lightness modification for a photograph to give natural impression as for the real scene, C. Phuangsuwan et al., Jr CSAJ 38 (2014) 180-181).
Study about the lightness L* from some text book. (Dr Phuangsuwan finds out the reference).
Aim of the experiment
When we want to develop photographs that exhibit the lightness constancy we need to know the relationship between the whiteness W and the lightness L*. No formula has been given for the relationship except an equation proposed in the above reference, which was not precisely determined. Yum will try to obtain the formula that can be used for a further research.