How to make sense of ancient Greek colours (2020)
I&#x27;m a little uncomfortable with the author&#x27;s insistence that hue, saturation, and value are objective physical measurements:<p>&gt; Outlined are the controls for three parameters which define the physical parameters of any colour uniquely. ‘Hue’ for the part of the spectrum the colour falls on; ‘saturation’ for the range from grey to vivid; and ‘value’ for lightness-darkness.<p>&gt; Hue, saturation, and value represent only the physical characteristics of coloured light.<p>I don&#x27;t think this is right. Hue, saturation, and value are statements about human perception, not about the physical characteristics of light. A description of the physical characteristics of some light would look like a histogram plotting the wavelength of the light against the amount of light present at each wavelength. How do you interpret HSV from that?<p>Well, value is pretty straightforward: the greater the area plotted in your histogram, the higher the value, I guess. More light -&gt; more value. This falls apart if we&#x27;re considering light of a single wavelength, where increasing the amount of light doesn&#x27;t cause the color to get more washed out.<p>Saturation is less straightforward, but the idea is there: a color with low saturation (greyish) should have a histogram that looks more or less flat, and a color with high saturation should have a histogram characterized by a lot of zeroes and spikes. The number of spikes in the histogram is... completely arbitrary.<p>Then we come to hue and our model completely falls apart. Hue is purely subjective and there&#x27;s no way to systematically relate it to light wavelengths.<p>The article comes close to suggesting that hue is objectively significant:<p>&gt; In the colour circle at the left, the direction from the centre represents hue<p>&gt; Most English speakers would be comfortable using ‘blue’ to refer to all of the top left quarter of the circle. But we wouldn’t feel nearly as comfortable grouping all of the bottom right quarter under a single term.<p>This is true, but it&#x27;s an artifact of an arbitrary definition of hue. You could change how much angular space is assigned to each color without causing any problems in the HSV model.<p>There&#x27;s another interesting claim in the piece:<p>&gt; Gladstone does make a starkly racist declaration that ancient colour systems are ‘less mature’ than contemporary English.<p>It seems pretty likely that Gladstone would have been happy to claim that he and the ancient Greeks belonged to the same race. Why is this a starkly racist declaration?