How's you color vision? (test)

[Simon Garrett]

Food for more thought there indeed, Simon. I wonder if Luma has an effect? After all, wide-gamut monitors are supposed to appear more "saturated" in some hues, are they not?

Interesting thought.

In the tests (or at least, all the ones I had more trouble with), the colours being displayed were all rather unsaturated, pastel shades. In those, at least, the appearance should be the same on wide or narrow gamut monitors (as they are likely to be within the gamut of all monitors).

However, although the colours may be the same on any (calibrated and profiled) monitor, the spectral composition will depend on the primaries of the monitor. For example, a narrow-gamut monitor might have a green primary roughly the same as sRGB (x=0.30, y=0.60) but a wide gamut monitor (my Eizo, for example) has a green primary about x=0.197, y=0.723.

In other words, whatever the calibration of the monitor, all the test patterns will be composed of various combinations of the R, G and B primaries for that monitor - which will differ from monitor to monitor.

However, I can't immediately figure out what that means for the tests. For example, suppose one is trying to distinguish between two pastel shades. Will it be easier if those shades are composed of some combination of 3 widely-spaced (highly saturated) primaries, or a different combination of 3 more narrowly spaced primaries? For a person with normal colour vision it shouldn't matter - the colour will be the same in both cases. But for someone with a minor color defect? I don't know enough to figure that out.

[xpatUSA]

Interesting thought.

In the tests (or at least, all the ones I had more trouble with), the colours being displayed were all rather unsaturated, pastel shades.

And I recall that the paper prints for the RAF eye-test were similarly shaded.

In those, at least, the appearance should be the same on wide or narrow gamut monitors (as they are likely to be within the gamut of all monitors).

However, although the colours may be the same on any (calibrated and profiled) monitor, the spectral composition will depend on the primaries of the monitor. For example, a narrow-gamut monitor might have a green primary roughly the same as sRGB (x=0.30, y=0.60) but a wide gamut monitor (my Eizo, for example) has a green primary about x=0.197, y=0.723.

In other words, whatever the calibration of the monitor, all the test patterns will be composed of various combinations of the R, G and B primaries for that monitor - which will differ from monitor to monitor.

However, I can't immediately figure out what that means for the tests. For example, suppose one is trying to distinguish between two pastel shades. Will it be easier if those shades are composed of some combination of 3 widely-spaced (highly saturated) primaries, or a different combination of 3 more narrowly spaced primaries? For a person with normal colour vision it shouldn't matter - the colour will be the same in both cases. But for someone with a minor color defect? I don't know enough to figure that out.

Don't know enough, either. A step might be to transform to CIELAB and then calculate color differences (delta-E) but that would be seriously anal, even for me

[Davidgypsy]

Come back, oh beloved 128K Macintosh with it's singing 3.5" drive and it's only connection being to the world's noisiest dot matrix printer . . .[/QUOTE]

And how many disk swaps were required to copy 128 Kb???

[xpatUSA]

Come back, oh beloved 128K Macintosh with it's singing 3.5" drive and it's only connection being to the world's noisiest dot matrix printer . . .

And how many disk swaps were required to copy 128 Kb???

Boy, that's a tough question . . . gosh, golly . . . ummmm . . . .

. . . and the answer is 0.32 disk swaps

Tell me you didn't think that the original 3.5 floppies were less than 128K capacity?