====== 2021-09-08 - shoe color ======

shoe colors? seriously? yes... but obviously not because of a shoe. interestingly, not quite about a color either... so let's start.

some time ago i was asked by a friend of mine, what is the collor of this shoe:

{{:blog:2021:09:08:shoe_color.png|what color is this shoe?}}

turns out that this was a fairly common photo sent around on the internet, around 1-2yrs ago.

it's pink to me. but it turns out that many ppl see it as gray, instead. so it got me thinking...


===== 1st approach =====

my 1st guess was that it's the same thing as with blue and green colors. the wavelengths of these two colors are next to each other, so around midway in between "perfect blue" and "perfect green", some ppl see "still green" yet others already interpret it as "already blue". it's not so obvious however with gray and pink (not to mention shades), as these are not monochromatic.


===== 2nd approach =====

these must be close to each other in color space, then! so let's see how our [[https://www.color-hex.com/color/c4aead|pink-ish]] and [[https://www.color-hex.com/color/808080|grey]] look like:

  * "silver pink" = 196, 174, 173
  * "gray" = 128, 128, 128

ok -- not exactly the same, but also not super far away...

let's give it a shot in another color model, namely HSL/HSV:

  * "silver pink" = 3deg, 12%, 77%
  * "gray" = 0deg, 0%, 50%

now the proximty can be seen much better! only the last parameter is off by around 1/4.

due to the above, there are some "shares of pink", like [[https://en.wikipedia.org/wiki/Shades_of_pink#Silver_pink|silver pink]] that could be considered a bit more gray. thus the confusion.