
Chromostereopsis (2002) - Tomte
http://www.ritsumei.ac.jp/~akitaoka/scolor-e.html
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tbabb
Best theory I've heard of this is that it's due to chromatic aberration in the
lens of your eye. Blue is deflected slightly to the left/right relative to
red/yellow due to the wavelength-dependent refractive index of your lens. This
deflection causes a spurious parallax shift on your retina which your brain
interprets as depth.

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ebg13
That doesn't explain the white/black background difference shown at the end.

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tbabb
Seems in agreement to me-- The white will contain red, green, and blue, which
will make a red-green fringe against blue, and green-blue fringe against red.

The sensitivity of the eye is also nonlinear, so bright-against-bright is
going to have far less contrast than bright-against-dark.

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pavel_lishin
Huh, I wonder if this is related to why all blue LEDs and Neon lights look
vaguely blurry to me, while all the other colors look fine. I honestly have
trouble reading anything at night if it's written on a building in blue; I
catch myself checking if I have my glasses on.

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ryandamm
This is due to dispersion, or ACA (axial chromatic aberration): your eye
actually focuses at different depths for different colors. This will be most
noticeable for large apertures (so at night, when your pupils are dilated),
and for extremely long wavelengths... like highly spectrally pure indigos,
like neon lights, or certain LEDs.

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pavel_lishin
Cool! Does this mean that if I shine a light into my eye, like looking at a
bright cellphone screen, I should be able to focus a little better on blue
lights for a minute?

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ryandamm
Sadly not; the lens in the eye is somewhat adaptive, but the 'blooming' effect
of bright, short-wavelength lights at night mean your eye is incapable of
focusing all of the rays onto a single small spot.

Unless, that is, the bright light (color irrelevant) causes your pupil to
contract. Then things will appear sharper and darker (until your pupil expands
moments later).

It's sort of amazing that biological eyes work at all, to be honest.

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shroom
I appear to be part of half the people. What does it mean for me?

Additional read
[https://en.m.wikipedia.org/wiki/Chromostereopsis](https://en.m.wikipedia.org/wiki/Chromostereopsis)

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curtis
I couldn't really see any of them until I started moving my head back and
forth a little bit, then they popped. The effect was really noticeable with
the red-black-dark blue images.

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DoofusOfDeath
I experience this occasionally with LCD monitors. The effects are most
profound when I'm using a terminal and there's colored text on a black
background.

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zero_iq
I don't think the display technology makes much of a difference (except that
maybe modern displays have better contrast than older ones). Can happen with
CRTs too. I first noticed this as a child with Teletext on British CRT TVs
back in the 80s, which often had bright primary coloured text on a black
background, much like a terminal.

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Jill_the_Pill
Does not work for me using f.lux at night and mono-vision contact lenses for
bifocal vision. In fact, in a few cases the blue looks in the foreground.

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ebg13
Try turning off f.lux? The colors matter for this.

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sigsergv
The only effect I see is "Vertebral column". Everything else is just plain
pictures without any “depth”.

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bobsil1
I’ve seen red links on black backgrounds pop out in 3D for years. Finally a
name for this.

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lvturner
Me too! Though I've really noticed it the past two or three years (maybe
because I've been using more 4/5k monitors?) I've been meaning to poll friends
for a while now to see if it was "just me" in a way it's a relief to realize
it isn't!

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ars
Sometimes happens to me with an OLED phone but not with any other kind of
display.

