The NAF range ruler is fine and I was wrong

The NAF range ruler is fine and I was wrong

The Internet is a great place for making bold claims based on faulty assumptions, so that's exactly what I did.  In my previous rant I claimed that the NAF range ruler was wrong, proving that two particular squares are the same distance from the thrower's square, but one is in range and one is out.

What did I assume wrong?

It turns out that the distance between the centre of the thrower's square to the centre of the catcher's square is not the right distance to look at.  The CRP  says:

"Next, the coach must measure the range using the range ruler, by placing the O at on end over the centre of the square of the player throwing the ball, and the red line that runs up the centre of the ruler over the centre of the square the ball is being thrown to. If the line between two passing ranges crosses any part of the receiving player’s square, the higher range should be used"

So we have to measure from the Thrower's centre, to the furthest part of the catcher's square (not the centre of it), but along the line through the centre.

Left to right: My centre-to-centre measurement, the real rulebook measurement, my new approximation.

 

Does this mean the NAF ruler is right?

I re-did the calculations to account for the extra distance to the far corner and I found that it is possible to get the same bands as the NAF ruler.  Because the real rule is tricky I made a small approximation, as shown above.  This gave a distance of 13.5 for (0,13) and 13.7 for (5,12).  A clear difference! As long as the threshold is between them, say 13.6, we can get the same range bands as the official ruler:

Spreadsheet available here

Why are you still mad?

Centre to centre makes way more sense, and is easier to calculate.