The Lab values are the same!
But the (rounded to integer) Lab values are not perceptually uniform! Besides, if by changing e.g. contrast between the slightly different RGB coordinates, the rounded integer LAB values do become different, it only proofs that they were not the same, they just looked the same.
Also, sRGB
[2, 255, 240] = Lab
[90.3139, -53.8885, -7.7599] if rounded to 4 decimals with a Reference White of D50, and sRGB
[1, 255, 240] = Lab
[90.3108, -53.9101, -7.7649] if rounded to 4 decimals with a Reference White of D50 (according to Bruce Lindbloom's CIE Color Calculator). Which shows their difference due to higher precision, and thus the silliness of the argument.
Visually the same does not mean that they
are the same. They only
look the same due to lack of precision of our instrument, our eyes.
Here is a chart of the variable resolution of our eyes by wavelength.
In fact, ColorThink using more precision than the PS values above report the dE between the two being 0.01, they are the same color.
No, they are not the same (dE==0), but they
look the same (dE<=1).
IF they are perceived as the same to the observer, they are the same color.
No, they are
perceived as the same color, but they
are not.
Unless you want to suggest color isn't a perceptual property.
No, that's nonsense, and I never said anything like that.
In any case, as far as the 'Standard Observer' is concerned, the two sRGB device values under discussion here are the same color when a dE 2000 metric is as tiny as 0.01!
So they
are slightly different, and thus not the same (although they will look the same).
Let's not fall in the trap of, "I cannot see it so it does not exist". Closing one's eyes, or not having the resolution to see the differences will not make things stop existing.
Edit: I built a two pixel PS doc with the two colors specified above. In ColorThink I asked it to extract unique colors. It extracted ONE color list.
And the precision was rounded to, how many digits, 2? Rounding to integer values or 2 decimals may be convenient for display, but it is far from precise, and can lead to wrong conclusions.
Cheers,
Bart