
What's Wrong with This Snowflake? - fortran77
https://www.npr.org/templates/story/story.php?storyId=121827582
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carapace
People who draw octagonal snowflakes freak me out a little, as do people who
aren't bothered by them.

It's like if someone drew a rainbow with four colors. Or a tree with square
leaves. Something is wrong with them.

~~~
beatgammit
Octagonal snowflakes are understandable since 8 is easy to make by folding and
cutting paper and results in a symmetric design. I can kind of forgive that,
especially if it's done as a crafting project.

What really confuses me is the 5-sided snowflakes. I really don't understand
where that comes from, and there's pretty much no basis for it in nature other
than starfish, which have practically no relation to crystalline structures.

I also get annoyed at restaurants that give children 4 crayons. I understand 3
(primary colors), 6 (primary and secondary colors), and _maybe_ 4 colors if
one is black, but I see red, blue, green, and yellow quite often. What
happened to orange and purple/violet? Is it really that much more expensive to
make two more crayons? It's like they mashed RGB with the primary colors and
called it a day. So if you're making a rainbow with 4 colors, I blame
restaurants that give out 4 colors of crayons.

~~~
amitp
Re: color — it's not just restaurants. Board games, card games,
Google/Microsoft/other logos, etc. also use 4 colors. Why?

Opponent-process theory ([https://psyc.ucalgary.ca/PACE/VA-
Lab/colourperceptionweb/the...](https://psyc.ucalgary.ca/PACE/VA-
Lab/colourperceptionweb/theories.htm)) says that the eye converts the three
wavelength inputs into six orthogonal axes (dark-bright, yellow-blue, red-
green). From these axes we get the four primary colors: red, yellow, green,
blue. Of course things are never so simple. There are various attempts to
measure the perception of color
([https://www.handprint.com/HP/WCL/vismixmap.html#ncs](https://www.handprint.com/HP/WCL/vismixmap.html#ncs)),
and none of them place red-yellow-green-blue exactly along the axes.

~~~
Kaibeezy
“Four primary colors” is bugging me like a 4-sided snowflake.

Can we agree:

    
    
      Additive - RGB
      Subtractive - RYB / CMY
    

I found this bit in the Wikipedia article interesting / relevant:

 _Thus for trichromats like humans, we use three (or more) primaries for most
general purposes.[25] Two primaries would be unable to produce even some of
the most common among the named colors. Adding a reasonable choice of the
third primary can drastically increase the available gamut, while adding a
fourth or fifth may increase the gamut but typically not by as much._

