... or the camera??
I bet you'd say that "naturally" the tripod-collar at the lens (in my case the Nikon AF-S 70-200/2.8G VR II) is the preferred option.
Well think again! The following image shows the results mounted on a very sturdy Manfrotto/Bogen 545B + 405 head with either mounting positions shot at 1/20 sec without mirror-up. So the mirror-slap is the only reason for any vibration:

on the left the lens is mounted on its tripod-collar, on the right the camera is mounted to the same tripod and the lens is left unsupported.
I wouldn't believe this if I hadn't seen it myself...
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Thomas (beware: Nikon-fanboy and moderator!)
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