So the discussion finally admits that different computer monitors, especially older ones, can affect the hue, saturation and contrast definition of displayed colours and should not be used for testing purposes......now, where were we on that CAD Test?????
As for Ishihara, I can see two numbers on several plates and it varies greatly with the lighting conditions as to whch is the clearer. If I am tested in daylight conditions as per the manufacturer's instructions then I see the correct stated number but if I am tested using a lamp, especially an old defunct lamp with a worn out bulb then I see the wrong number.
Interesting?