In article , PeterN
wrote:

I am not too sure that ³shutter speed stability² is the term you are
looking for. This is the first time I have heard it used.

If when shooting handheld, and you have a static target/subject, relatively
slow shutter speed (usually slower than 1/120-1/80), and a longer focal
length IBIS, or ILIS (IS/OS/VR) is going to be a great help.The greatest
benefit will be found with handheld landscapes, or portraits.

When it comes to moving targets/subjects a shutter speed, direction of
movement relative to the photographer, and camera handling techniques are
going to be far more beneficial than any mechanical stabilization. The only
time stabilization can help with a moving target/subject is when the movement
is directly away, or towards the photographer. When shooting with a panning
motion the camera is stabilized by the inertia imparted to the camera system
by the lateral movement of the camera tracking the target.

i am talking about shooting fast moving objects, at a high shutter
speed. I agree that IS is indispensable for slow moving objects and when
shooting at slow shutter speeds.

stabilization doesn't do anything for subject motion.

stabilization helps *camera* motion, generally when shooting at slower
shutter speeds. it can be used at higher speeds, but it's not as useful
and can potentially alias.