Re: In-lens VR/I.S. must be eliminated

Chris Malcolm wrote:

>> Totally incorrect!  Your statement would only be true if *ALL*
>> lenses had its final element set at exactly the same distance from
>> the sensor plane, which they do not!
>
> The distance of the final element is irrelevant, what matters is the
> distance of the centre of focus. That's what effects how one degree of
> wobble in camera direction translates into lateral movement of the
> image across the sensor.

Not for in-camera IS/VR.  A simple analogy is teeter-totter (fulcrum). 
Take
a long lens for instance, 400-600mm, have their final element much further
away form the sensor plane than say a 50mm.  This final element is like a
fulcrum and on longer lenses p***** a much higher degree of movement
across
the sensor.  The sensor must work harder, faster, and move farther to
neutralize this movement.  This is why in-camera stabilization is
impractical for long lenses.





Rita