Petone

I'd had the 70-300 for about a year now. Unreliable focusing - especially at 300mm end. often focus behind subject is static and in center of frame. Infuriating with birds for example! You think you have a bang-on sequence of several shots and they often all turn out out out of focus. I try shooting short bursts, then refocus and shot another burst - this has often saved me - but man this gets frustrating! :-(