Sergio, I ran a similar test with a small cup of water on a 1Ds on a Bogen 441 tripod with similar results. I found that if I firmly pulled the legs apart as far as they would go against the stops, and put some weight on the whole thing, much of the vibration disappeared. I have now added a 1/4x20 eye bolt to the bottom of the center column so that, with the aid of a carabiner, I can easily hang my camera bag there.

Give this a try and see if it helps, and have a great trip!

Michael, I made your test using a 1Ds + 70-200 2.8 IS (off)Acratech ballhead + Bogen 3021 legs. Shutter set at 1 sec. MLU on. Self timer at 10 secs. And the glass of water. There are two moments where there is vibration. One is small but it´s there which is when the shutter opens, and the second is big (doesn´t matter - when the mirror goes up).

Do you have this first small vibration in your system setup?
And if you have it, have you noticed image degradation because of it?
What technique do you suggest when working in high winds?
It is very difficult to avoid windshake.
I will be going to Ecuador volcanoes in Jan for an 8 day shoot, and the wind issue concerns me because I will be very high up (4000 mts+) and it will be unavoidable.

Maybe a rice bag (fill it with on the spot sand) could help.
What do you think?

Thanks,

Sergio