Many people believe that VR and other image stabilization systems should be turned off above 1/500. The reasoning behind this believe (because thats' what it is) is that the sample frequency of the VR system is not high enough to 'resolve' the data higher shutterspeeds can register. If you think this sounds strange than don't blame me, I'm just trying to explain what others think or write about this. While there are cases where switching VR off may be advisable, I don’t believe they are related to the sample frequency. Neither is there any reason to panic about the combination of VR and higher shutter speeds: even with D800 at 1/8000s there no resolution difference measurable. (proof of this on the next page)
VR (sometimes called OS or IS by other manufacturers) is a system that tries to counteract vibrations, better: camera movements. Camera movements will cause blur, if during exposure an image point will move over a greater distance (angle) than the camera can resolve.
The idea behind VR is quite simple: when the camera moves e.g. to the right, a slight movement of a lens(group) (or camera sensor, in some cases) to the left will make the resulting movement smaller than the camera resolution.
What does the system do? It uses accelerometer sensors to measure the movements. It samples the data of those measurements (in the case of Nikon) every 1/1000 of a second - at least according to some sources. Nikon doesn't confirm this, but it's a very common sample frequency for accelerometers. PART 2 >> (with pictures)