The other night I was taking long exposures on the 27th floor balcony of my hotel room. I noticed a slight vibration in the railing (I figured it was attributed to the wind, cars driving by, the hvac system, elevators, etc), and was thinking there might be a slight vibration in the balcony too (it was concrete & steel).

Would the image stabilization be able to counter those vibrations? My camera was on a tall CF Induro tripod, with the camera bag providing ballast under the center post. The exposures were 10-15 seconds, wide open, Canon 6D, mirror lockup, Canon 35 IS Lens (and the new Tamron 90 VC) and the IS was off. I didn't notice any movement in my images, but the exposures weren't long enough for me to notice if there were going to show up.

I am not really worried about the vibrations, just more of a question from my engineering mind....