3 ms·

"The distance from your eyes to your thumb is *about 10 times* the distance between your eyes." Which means you could calibrate this formula using your own bod

• kqr 4y ago
  12.5 sounds to me more like measurement error than natural variation. Did you measure the eye distance between the centres of your pupils?
  • deleted 4y ago
    [deleted]
  • thfuran 4y ago
    You don't think the original claim of an even ten sounds a lot like rounding?
• indigo945 4y ago
  If you have trouble measuring your pupils distance (which is hard), you can also just calibrate using a set of known object sizes and distances.
  • AlexanderDhoore 4y ago
    That is exactly what I did. I placed a ruler of 40cm on a closet at eye level. I did the thumb trick and found the exact distance I had to stand so my thumb jumped from left to right of the 40cm ruler. Then I measure the distance I was standing from the ruler. distance / 40cm = your body ratio. So there is no reason to measure length of arm or distance between eyes. We are only interested in their ratio here. You basically run the "thumb trick" in reverse. From the distance and object size => you get the ratio.
    • credit_guy 4y ago
      This is awesome. It's a cool way to teach your kids both math and science. Math because of the triangle similarity proof of the "recipe", and science because of the method of calibration. Thank you.
• navane 4y ago
  Did you keep your shoulders facing the object, or did you rotate one shoulder towards the object?