Want to capture kids' happy expressions? Capture them doing something fun. And what kid does not like to swing.
I was not getting good results using AI Servo focus mode on this camera and lens combination (primarily a lens issue here), so I opted to use One Shot AF and take the shot at the moment the pendulum motion stopped on the back-swing. My in-focus hit rate was decent using this technique.
The 85mm f/1.4 setting allowed the background to be strongly blurred and allowed for a fast, action-stopping shutter speed on this heavily overcast day.