05-30-2016, 10:08 PM
My take is it the OS lens magnetically suspended by the stabilization system. My Nikon AF-S 70-300mm VR II has a fault and does not work in stand-by mode, when you focus and use half-press the VR system stabilizes nicely and all is sharp. When you let go the viewfinder image goes "clunk clunk" and the VF image drops, if you take a picture in this situation the image is de-centered and soft!
So the OS lens needs to be electrically suspended in a neutral position even when the OS is in the off position.
Modern giros have no motors but are minute crystal ceramic tuning forks that bend slightly when subjected to accelerations, this bending creates tiny electrical voltages which are fed to the electronic circuits/ electromagnets, the humming is the frequency of the OS system.
So the OS lens needs to be electrically suspended in a neutral position even when the OS is in the off position.
Modern giros have no motors but are minute crystal ceramic tuning forks that bend slightly when subjected to accelerations, this bending creates tiny electrical voltages which are fed to the electronic circuits/ electromagnets, the humming is the frequency of the OS system.