No, but then I've never used the Z head. So if your L bracket is properly tightened, and your head is solidly tightened to the tripod legs, and your head or head clamp isn't malfunctioning, you've probably got something wrong with your camera...
Well, the issues of tripod and heads may turn out to be less clear-cut than i had remembered or reported here. So just to keep my account in order...
First time around (April), i didn't understand why i was seeing such poor results from the Phase 150mm, so i sent the equipment back, with comparative files for Phase to look at, and I waited to see what conclusions arose. In this instance, i had worked both cameras alternately on my tripod. At this point i was assuming the issue was with the lens, and was happy to accept i might have made a mistake... or been unlucky. There was general agreement that the older H lens was (surprisingly) better, but also a firm belief that the Phase lens was
the better lens... and widely respected / loved etc. Mmmm.
Two months later, my dealer kindly drove out to me, to re-do the test with another 150mm lens, but this time, i shot with my H system on my tripod etc... and here is the bit i'd overlooked, he shot the DF on his tripod and head. Now i know his kit looked much like mine, (also Gitzo, also carbon fibre, and i think also an Arca ball head), but as i have said before... i don't pay too much attention to equipment unless it is mine and i need to use it. It turns out that he may well have used his centre column!
That doesn't explain away why the results were so poor first time around, but admittedly, it does warrant revisiting the second test.
Either way, it seems reasonable to assume that whatever is going on, is probably more to do with the body with
the longer lens, rather than the just the lens itself, and i continue to wait for a response from Phase One.
Apologies for overlooking the details above.
For those interested, I'll let you know the outcome...