Thanks, Frank.
The lens is about 240mm Focal, so it's not too long. As such, it is possible to rack out the rear extension, leaving the weight of the lens/iris fairly close to the tripod point.
Would eye put a 360mm f6.3 on it and rack it out to full extension? Nah (although I suspect that it could take it for a short shoot). But I will be looking at a 360-400mm tele for it.
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