I'm using an XL-H1 which depending upon the lens/accessories in use weighs about 4-6 kg. I'm about to upgrade my tripod and wonder whether (all other things being equal) I would be better off with a tripod with a 100mm bowl as opposed to a 75mm one.

I regularly use high magnifications (40x or so) for birds in flight and perhaps a 100mm bowl is better from that point of view. Some informed comment would be very welcome.

Many thanks

Paul

Personally, given the option for long lens work I'd go for 100mm, they're usually more stable legs and tend to resist the "winding up" torsion that can spring back on you at the end of a pan. However, I'm a bit odd in that use my old Ronford F4 on my Sachtler Horizon head's 150mm carbon fibre legs with prosumer cameras like the JVC HD 100 and the Z1. One big advantage being that it's so fast to set the thing up, the legs just drop without having to be pulled out.

As Brian says, it's not necessarily the bowl size that works better but the larger build of the legs in general. So don't buy a CHEAP 100mm bowl tripod instead of a well built 75mm but I suspect you'll do much better with a 100mm set-up.

Even though quality 75mm legs are pretty good, I would go with 100mm legs if you use a lot of tele, but don't skimp on a 100mm tripod either. The dead cheap ones tend to flex more than a good 75mm and will wear out much faster...so skip any Libec gear...