Hi Donoreo,
On the 70-300 IS lens when you look through the viewfinder, before half pressing the shutter button, the natural shake/vibration caused by the human body is visible but when half pressing the button the shake/vibration is markedly slowed down. That's what I meant by movement.
The noise, and lack of it on the 18-55, I spoke about is mentioned in this this review I just found.
"I've always been a big fan of image stabilization - the big feature upgrade this lens has over the 18-55 II. The Canon EF-S 18-55mm f/3.5-5.6 IS Lens utilizes a new, smaller IS design based on the IS mechanism used in the PowerShot SD700 IS Digital ELPH. This new design features automatic panning detection (formerly mode 2) and is tripod sensing.
While most IS lenses makes a humming sound of some level, this one is silent. If you put your ear against the lens, you might hear some faint clicking sounds, but you need to make an effort to hear them." - taken from this article :
http://www.the-digital-picture.com/r...ns-review.aspx
My post should have said I've tried taking identical shots with the IS switched off and on, but can see no noticeable difference. I'll try taking more shots.
Looks like it's me that's not working, and not the lens!!
Thanks for your help.