Using the thumbscrew-type lock frees the tilting of the center column once it's been extended past the chassis, which becomes possible once you press a button at the column's bottom to disengage the safety bolt. Once it's extended, the column can tilt, with no ratcheting, from its original 0°, straight-up-and-down orientation all the way over to a 180° upside-down orientation – with possible stops everywhere in between, including a 90° lateral position. Twisting a knob on the chassis locks and unlocks the 360° swiveling of the center column and its upper collar.
The tripod's flip locks, which enable the extension and securing of the leg stages, are user-adjustable. By using a supplied Allen key the user can tighten two points on each spring-loaded flip lock to safeguard their continued reliable performance.
The BC-1's multiple knobs enable higher-precision adjustments to the head than are possible with single-lever heads. Panoramic photography is well-served, for instance, because you can pan a specific number of degrees while keeping the head's tilt position locked. In fact, the BC-1 features degree markings around its circumference to aid in that task.
The tension-control knob accommodates the varying requirements of lighter and heavier camera setups, as well as the preferences of individual photographers as they adjust and readjust their camera's orientation. At any tension level, the locking of the head's ball is remarkably strong.
The included quick-release plate attaches to your camera via its standard 1/4"-20 screw. The BC-1 head features an Arca-Swiss-style clamp for securing the quick-release plate. A rubberized knob controls the opening and closing of the aluminum clamp simply and reliably. Two studs on the bottom of the plate help prevent the camera & plate from sliding all the way forward or backward out of the head, in case the clamp is inadvertently left loose.
When not being used in its lateral mode, the AC-2320LA's rapid center column functions like you'd expect from any professional tripod, extending after a twist of the knob on the upper collar. For protecting your camera when the column is retracted quickly, there's a rubber damper under the center-post collar. Anti-twist steel locking screws underneath the center-post collar enable you to fasten the camera head securely.
Pull-in/push-out positive leg locks allow positioning of the three legs independently at three different angles. This permits shooting at low angles or on uneven terrain. For stability on softer terrain, the AC-2320LA features metal spikes that extend and retract by twisting the foot's rubber tip.