July 21, 2026 at 2:05:05 PM UTC

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I was curious what the red/yellow cards used in the World Cup would look like with color vision deficiency (Protanopia shown).

Seems like a player could be shown a card and not know the color. Does it matter with sufficient contrast and only 2 cards?

Could be easily solved by adding a symbol.

An official referee holder for red and yellow cards, with the cards peaking out. A comparison is shown simulating Protanopia, where both cards are a muted shade of yellow.

Also posted to Mastodon.

21 replies

Tom Hicks Bluesky 35 min later

I think they had oval shapes red cards for a time.
1. Zach Leatherman Bluesky 39 min later
  
  really! fascinating. en.wikipedia.org/wiki/Penalty... shows a triangular card
  1. Tom Hicks Bluesky 41 min later
    
    Here you go! www.ebay.com/itm/17683169...
    1. Zach Leatherman Bluesky 45 min later
      
      awesome, thanks!
Nils Hörrmann Mastodon 39 min later

@zachleat In German, we have the colloquial term "Arschkarte", the "ass card": "To avoid confusion, football referees often keep the yellow card in the chest pocket, while the red card is in the back pocket. The player to whom the referee shows the red card would then have 'got the ass card.'" (https://de.wikipedia.org/wiki/Arschkarte)
1. Zach Leatherman Mastodon 46 min later
  
  @nilshoerrmann ahaha I have noticed this but in my experience it seems inconsistent!
2. nilsmielke ⁂ Mastodon 59 min later
  
  @nilshoerrmann @zachleat Dang, Nils, you bested me by 5 minutes. 😅
  1. Nils Hörrmann Mastodon 1 hr later
    
    @nilsmielke @zachleat Sorry 🏟️
    1. Nils Hörrmann Mastodon 1 hr later
      
      @nilsmielke @zachleat I always found this term funny, especially if it really dates back to black and white TV …
      1. nilsmielke ⁂ Mastodon 1 hr later
        
        @nilshoerrmann @zachleat Same. (So obvious in a way, though. 😊)
damianwalsh Mastodon 41 min later

@zachleat
1. Zach Leatherman Mastodon 46 min later
  
  @damianwalsh ahah exactly!
nilsmielke ⁂ Mastodon 44 min later

@zachleat Are they not still storing the red card in their back pocket?
AFAIK that card placement was established in times, when there was only b/w TV.
Don’t know, if that’s a thing in the English language, but that’s why we use the term “Arschkarte” (“ass card”) in German for when something went wrong.
1. Zach Leatherman Mastodon 48 min later
  
  @nilsmielke ah, yes! I have seen this but it doesn’t seem consistently applied to me? maybe a solved problem though!
Martin Grubinger Bluesky 1 hr later

There's a german saying "die Arschkarte ziehen" which apparently comes from referees pulling red cards from the back pocket and yellow cards from the shirt pocket to make it clear on black and white TV.
[citation needed]
1. Zach Leatherman Bluesky 2 hr later
  
  The Ass Card™!
jasonkarns Mastodon 2 hr later

@zachleat imagine being color blind and playing where both teams’ kits are indistinguishable
1. Zach Leatherman Mastodon 4 hr later
  
  @jasonkarns maybe your team could wear a special scent to help 😅
  1. Private reply Mastodon 5 hr later
    1. Private reply Mastodon 5 hr later
Matt Mastodon 9 hr later

@zachleat If we're putting symbols on them can we get Uno to sponsor the world cup?