■ AF systems, even those on vintage SLRs, are remarkably capable. They might rack back and forth a little in their search of sharpness, but generally speaking, most will do a fine job.
If there was any weakness it was with fast-moving subjects, especially if they lacked hard edges and contrast. Such is the rate of progress, however, notably on mirrorless cameras, that the latest AF systems are capable of speedily acquiring and holding sharp focus, on moving subjects, assisted by eye-tracking and subject-detect. What’s more, they can do this even with fast continuous shooting speeds so every frame in a sequence can be sharp. Current AF systems are so good that photographers with limited experience of shooting action can get great results.
Four cameras show off their continuous AF tracking skills