Colorblind and 3D vision?

February 18, 2011 10:38 AM

Can people with red-green colorblindness see depth in 3D comic books where you look through red-blue glasses? Personal testimony from my colorblind readers would be most compelling to me, as the optics are complicated.
posted by tnygard to Media & Arts (6 answers total)

Yes. The differently-coloured lenses in front of each eye still perform their function of filtering the original combined image into left-eye and right-eye parts, even though the wearer can't distinguish between those colours. The filtering occurs before the light even reaches the eye, so the wearer's colour perception doesn't enter into it at all.

A similar principle is used to allow colour-blind people to read things like wiring diagrams with colour-coded lines on them. A selection of filters held up in front of the diagram allows them tell if that's a red wire, because it disappears when a red filter is in front of it.
posted by FishBike at 10:42 AM on February 18, 2011 [3 favorites]

We don't exactly have distinct "red" and "green" receptors (of which red-green colorblind people are missing one). The receptors responsible for red and green perception have quite broad response curves, that is, they mostly overlap. We distinguish red vs. green by the fact that some light affects one of the receptors more than the other. If we don't have one of the pair, the whole spectrum of light is still perceptible, we just can't tell as much about what color the light is.

Blue is a bit different; it has a narrower response curve, off in the shorter wavelengths. Presumably someone who only had the blue receptor would actually be unable to see light in the longer-wavelength red/yellow area of the spectrum. But AFAIK "blue-only" isn't a form of colorblindness that actually occurs in people.
posted by hattifattener at 11:28 AM on February 18, 2011

The people who have most trouble seeing 3-D images are people who have issues with stereoscopic vision. Like me. I have never seen a 3-D image in any 2-D medium, though I am not stereoblind in actual life; my eyes just don't work with the glasses.
posted by Sidhedevil at 2:22 PM on February 18, 2011

I want to say that I have read somewhere that there is blue-yellow colorblindness. I don't know what effect that has on this question, however. Also: there are a few forms of red-green colorblindness, not just one, so the answer to this question might not be quite as straightfoward as one might think. Or maybe it is.

I do question whether this answer would change if you were trying to see something in 3D on a screen. Someone I know with red-green blindness has no problem distinguishing between the two in print, but when the colors are on a screen or monitor, he sometimes can't tell that there is even text there if the intensity of one color is too close to the other. Same with traffic lights...they just disappear.
posted by vivid postcard at 4:44 PM on February 18, 2011

But AFAIK "blue-only" isn't a form of colorblindness that actually occurs in people."

It's called blue cone monochromacy, and it's very rare.
posted by topynate at 5:48 PM on February 18, 2011 [1 favorite]

I have a color deficiency and I see 3d fine. I cannot tell red from brown from green or blue from purple. The old 3d glasses with one blue one red lens work fine but give me roaring headaches if I watch movies with them but 3d print is fine. The new polarized lenses allow me to watch movies without a headache.

I have never been able to see 3-d stereograms though. Not even ones without red/green.
posted by M Edward at 9:01 PM on February 18, 2011