During vacations and travel I tend to use my Nikon D90 and a 18-200 VR (image stabilisation) lens.
I was very annoyed (and had no explanation) when I found images to be unsharp, which had be made in wide (20-30mm) and very fast shutter times (1/800s).
The images obviously had been unsharp from camera shake, but this was improbable if not impossible at 1/800s and 30mm using an VR/IS Lens.
Later someone told me he read somewhere in the internet that VR lenses tend to blur pictures at very short shutter speeds like mine.
I paid more attention to it, and my blur problems all are with VR lenses at very fast shutter speeds.
So I'd like to know: why to VR lenses blur pictures? At what speed do they ruin my pictures? Is there anything to do about this apart from disabling VR or better not buing lenses with VR/IS?
(interesting side note: as far as he told me only systems with VR/IS in the lens are prone to this problem. Systems with IS/VR in the DSLR Body do not have this problem).
Answer
As it is when questions are burning me, I searched the web for more information about this and found a very good article by Thom Hogan explaining the Nikon VR system (and it's limits):
His findings explain my problems: he says to be careful with VR with shutterspeeds of 1/500s and below, since these are prone to problems since they come too close to the sampling rate of the VR system.
Due to the pitfalls of the VR system he recommends disabling VR if you don't need it.
The article is a very good read, it explains a lot of details of VR, the difference between normal and active VR, VR and the new VR II, how to use VR when panning or standing on a moving platform...
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