Virtual course: Control #8

The description ‘Between’ two features has two requirements for the control point:

It is on the shortest line between the features, simple enough in this
case but sometimes more difficult with area features.
It is exactly midway between the edges of the two features at flag
height, in this case between the trunks of the trees.

In the photograph the middle flag can be seen to be on the line joining the two trees, so the first requirement is satisfied. But is it at the halfway point? The photograph suggests Flag B is off-centre but this is an illusion, due to foreshortening as the left-hand tree is further away. An allowance can be
made for the foreshortening but is better if the control can be viewed from a point on the track further to the left.

In this example it is relatively easy to decide that the middle flag is at or very close to the control position and is therefore the correct answer. In more complicated control sites of this type there may be several flags in the vicinity of the mid point, which therefore has to be estimated with more precision.

Note the direction of view arrow in Column H. This informs competitors that they have to go along the track beyond the control to find the marked decision point.

Solution: Flag B.