The Mystery Of Tetrachromacy (color vision stuff)

[Telecaster]

A new article on tetrachromacy…that is, having retinal cones with four wavelength peaks rather than the usual three. In theory this should allow for vision with much finer tonal gradation than most of us experience. This is the first report I've read of any genuine study of the phenomenon.

IMO the report sometimes oversimplifies but overall it's informative and well worth reading.

http://theneurosphere.com/2015/12/17/the-mystery-of-tetrachromacy-if-12-of-women-have-four-cone-types-in-their-eyes-why-do-so-few-of-them-actually-see-more-colours/

-Dave-

[Zorki5]

Many thanks for the link! Not only it's interesting, but it has... practical implications for me

After reading through the article, I firmly believe my wife is not only a tetrachromat, but she's in the 1/7 of those tetrachromats who have clear separation of M-cones allowing them to actually see extra colors.

My color vision is perfectly fine. When going through color tests, I could always see color separation absolutely perfectly, as clear as if, say, some of the circles forming a shape were black and other white, forming a perfectly discernible shape.

And yet we have constant arguments with my wife about things like the color of the stripes on a shirt, or whether shirt color matches that of a waistcoat! In fact, last disagreement happened this past Thursday. It is almost always about tints of red, or colors having red in them (such as magenta), with my wife apparently seeing [larger] differences where I don't -- perfectly in line with what the article suggests should be expected.

[Telecaster]

Many thanks for the link! Not only it's interesting, but it has... practical implications for me

After reading through the article, I firmly believe my wife is not only a tetrachromat, but she's in the 1/7 of those tetrachromats who have clear separation of M-cones allowing them to actually see extra colors.

Wow. Your wife may want to consider having her color perception tested…assuming she's interested, of course. 

-Dave-

[Rob C]

Interesting topic, and one with which I agree insofar as I have seen the better colour vision of women at work. You can't be in the fashion trade very long before you become aware that women are much better at matching different garments to make a pleasing whole.

There's always the caveat that you might, as a male, simply be accepting their better vision as a reality without being able to prove it, but I don't think that's the case.

I also think women have better colour memory in the sense that they seem capable of buying something to go with something else without having the first piece of colour to hand when buying the match for it. In my own case, the way I remember colours is often light years away from the reality that hits me next time I see whatever I had been remembering.

Have you ever stopped to consider the many different shades of nominal 'silver' that cars can have? Few match the perfection of the Mercedes 'silver arrows' look; in fact, some silvers look suspiciously dull grey! ;-)

Perhaps that's partly why I prefer black/white photography, apart from the debilitating cost of any Mercedes that I would actually like to own.

Rob C

[Telecaster]

But note, Rob, that functional tetrachromacy is rare. Less than 2% of women by current estimate. Most tetrachromats don't appear to see any differently than we trichromats.

-Dave-

[Rob C]

But note, Rob, that functional tetrachromacy is rare. Less than 2% of women by current estimate. Most tetrachromats don't appear to see any differently than we trichromats.

-Dave-

Indeed, so it indicates, but from my own observations I'd still credit women with far better colour vision. Whether I've met an unreasonable number of special ones is anybody's guess!

;-)

Rob C

[amolitor]

I'd be interested in an analysis of the neural processing that happens for tetrachromats.

Also, more grist for my little personal crusade to the effect that color management is mostly BS.

[digitaldog]

Also, more grist for my little personal crusade to the effect that color management is mostly BS.

Probably because you don't understand that color management is number management.
Good luck on that crusade, like so many over history, they are medieval in their mindset. 

[amolitor]

Sure, but the perceptual goals, as understood (albeit extremely vaguely) by the vast majority are in fact not achievable.

Simply sloshing numbers in model to another is all very well, and you can certainly do it precisely or imprecisely, but if you people don't actually see colors in a consistent way, then the whole exercise, while jolly good fun, has utility only up to a point.

[digitaldog]

Sure, but the perceptual goals, as understood (albeit extremely vaguely) by the vast majority are in fact not achievable.

Colorimetry is about color perception. It is not about color appearance.

[amolitor]

I am pretty sure that's what I just said! So glad we agree.

[digitaldog]

I am pretty sure that's what I just said! So glad we agree.

It isn't what you said, and where we violently disagree is this:

Also, more grist for my little personal crusade to the effect that color management is mostly BS.

Just what one expects from a self admitted crusader. 

[amolitor]

Possibly I had appearance and perception reversed but we are in angels on pinheads territory at this point. Yes yes it's a super important distinction. It always it is.

[digitaldog]

Possibly I had appearance and perception reversed but we are in angels on pinheads territory at this point. Yes yes it's a super important distinction. It always it is.

So it's pinheads or super important? Never mind. Stick to Intermediate Photography and medieval crusades.

[NancyP]

How discriminatory is that X-Rite online color vision test (line up the color blocks)?  I assume that it is pretty easy, since I can do it quickly and get 100%. I have always thought that my color vision was "average", and that I just trained myself to pay attention.

Interesting article on tetrachromacy.

[digitaldog]

How discriminatory is that X-Rite online color vision test (line up the color blocks)? 

Kind of, sort of OK. It's not anywhere as effective as doing the test with actual tiles under an appropriate illuminant. The qualities of your display and it's calibration play a role on-line. If you have a really poor score, it's a indication something is iffy (you or the display or both).

[amolitor]

So if I take a picture of an apple and use a top drawer color managed workflow to make a print, what percentage of the population can I expect to say the the print matches apple?

It's not everyone. I mainly want to impress women with my apple photos so it looks like I've got problems here.

[digitaldog]

So if I take a picture of an apple and use a top drawer color managed workflow to make a print, what percentage of the population can I expect to say the the print matches apple?

You're asking a rhetorical question that can't be answered and you've still failed to understand the underpinnings of digital color management and the vast differences (again) between Colorimetry and color perception.

[amolitor]

I dunno, it seems like the answer could be obtained pretty easily with a short survey involving an apple, a print, and a group of volunteers.

Since this is precisely what the average rube thinks his new color munki spyder thing is supposed to do for him, and adding to that the fact that experts become surprisingly evasive when asked these sorts of simple questions, perhaps one can begin to understand my position.

[amolitor]

Also, is colorimetry about color perception (reply #9) or is there a vast difference between colorimetry and color perception? (Reply #17)?