Thanks. The lens locks firmly into extended position, no ‘wiggle’ at all. The leak appears (looking through the camera from behind) in the 4 o clock position, where the mechanism to twist and lock is, so not a good place to address from the inside. I’ll try a hair band or something similar on the outside of the barrel. There is significant play in the plastic DOF collar on the lens itself, though I can’t see that would have any effect. I’d be very loathe to part with A$300+ for another with the meter on top, purely b/c there seems little guarantee i wouldn’t be trading one problem for another.