Posted: Aug 08, 2017 8:46 pm
by GrahamH
romansh wrote:
Again I am simply asking is the bus's surface the same red as I perceive and if so why?


No. The question is a category error. Pigment on a surface is not neural classification of spectra. How could they possibly be 'the same'? Are they well correlated? Yes of course. In that sense you accurately identify the bus as red. You can functionally discriminate like and contrasted colours.

Consider that you measure the colour of the bus with an instrument that gives RGB readings of 200,15,9. Can you ask 'Is the surface of the bus the same as 200,15,9? Surely not. You can use the values to compare colours of other objects. You know the readings will change is the illuminating light spectra changes. The values are only a reference to the paint, a perception of colour, not a pigment on a surface. Ditto with your perception of colour.