Find the Odd Disk

Got 18/20. I chalk that up to spending years as a graphic designer. I'd like to see a similar study about which text was perfectly kerned, or by how many pixels an element was off-center or misaligned. I can spot that on billboards a block away, and my life is therefore a constantly grating experience.

Marginally related. I paint oils as a hobby, and my studio gets northern light, usually overcast and cloudy, during the day. Differentiating tiny color variations under those conditions is very easy, and in general your objective "pitch perfect" impression of color is also pretty accurate. However, I've painted in the same room at night under a "warm" LED bulb, and been absolutely shocked at how wrong and blue everything turned out when seen in the light of day. Not just that, but the hues I intended to be close to one another are much farther apart than they appeared under LED lighting.

So if lighting conditions can shift not just your perception of a color, but also its relationship to the ones around it, then I think how much more does your screen gamma and range alter that? A fair test would be printed on the exact same Heidelberg in 4 colors.

Regarding the LED lights: unless you use a lamp with CRI < 90, you see obvious, glaring color distortions, and some colors just "disappear", cannot be seen, because of the lack of a particular spectrum bands. Sadly, most inexpensive LED lamps have CRI around 80, and that light feeld definitely artificial, even if pleasant to the eye. A lamp with CRI 90 is okay, most things look natural, even though you can notice it's not sunlight. A lamp with CRI 95 is very fine, it's practically sunlight, and most tricky colors are visible well. I've never encountered a lamp with CRI, say, 97, but they exist and cost a lot.

(Source: doing object photography.)