Waypoint Settings

I have just started using APM Planner 2.0 with my Macbook Pro i7, 10.9.2. First couple of test missions have gone well.
Just a few things I would like to understand further about my auto flights. One of my waypoint settings I have set Iris to do 2 turns. However, the turns are big circles about 5m in diameter. Not sure if this is normal or not. I was expecting Iris to hold GPS position and just spin around or close to the point.

Any ideas from anyone?
Thanks.

I have check Loiter Radius and it is set to 0.