Photographing dragonflies in flight is always a challenge. As with most small, fast-moving subjects trying to track a moving dragonfly is often beyond the ability of either the photographer or the camera’s autofocus system.
Instead I prefer to approach the issue by looking at subject behaviour and then pre-focussing, i.e. setting the composition up and letting the subject fly into the frame. This particular image was captured at Langford Lakes in the Wylye Valley in Wiltshire. I noticed this Migrant Hawker pausing briefly in flight above a particular clump of reeds in front of one of the bird hides and by watching the repetitions of behaviour I was able to predict where to aim the lens for a close-up shot.