2.2 Challenges for the refree
One of the challenges for referees is that the human eye
can handle only approximately 16 images per second,
which means the ball needs to be behind the line for at
least 60 milliseconds. However, in some cases the ball is
only behind the line for a few milliseconds before a player
kicks it back or it rebounds back into the fi eld of play,
with the result that the human eye cannot see whether the
ball has crossed the line.
Another challenge is the vantage point. When viewed
from certain angles, it is easy to misjudge the ball’s
position. Cameras placed at different angles can mislead
viewers when showing images “proving” whether or not
the ball has crossed the line, which is why only technology
dedicated to evaluating such incidents can support the
referee in the decision-making process and contribute to a
fair game.