back 10 year ago the excentricity of the ball lent itself to the occassional lock up even with the control in a loosened position. this happened in travel situations and the ball curvature acted as a wedge and the ballhead being moved about or continuous vibration "wedged" it in. this required a considerable effort to undo at times. they have redesigned the balls curvature and it no longer has this issue.
i am using both the BH55 for the past 3 years and BH40 for the past year. in the years between the B1 and the BH series heads i used a Markins M10 which gave me good service. i tried out a acratech ultimate but its design and i did not get along at all the courtship lasted 3 months and ended abruptly
Ugh, it has that double-decker clamp that doesn't cam the plate against the bottom of the clamp...it's always surprised me that Kirk and AS design some of their clamps this way.
the plates go firmly up against the bottom of the clamp there is plenty of contact for any camera or lens combination you are likely to mount using everything short of an Arriflex motion picture camera rig
So why have the center channel? Arca-Swiss also now has a a narrower width QR plate option that is the same width of the rail on their large format view cameras.
Just because you don't need it means that it is a flaw.
Drew_Persson wrote:
Ugh, it has that double-decker clamp that doesn't cam the plate against the bottom of the clamp...it's always surprised me that Kirk and AS design some of their clamps this way.
Wouldn't less surface area, as pictured above, create a tighter joint between the two pieces, thus more friction?
