The Sirui K-40X Ball Head is
an extremely sturdy head with control knobs for pan, tilt, and tension,
plus an Arca-style clamp for the included quick-release plate. The pan,
tilt, and quick-release knobs are all separate, while the tension knob
is integrated into the ball-locking (tilt) knob. The head tilts 90° for
portrait orientation. There's also a video pin on the plate to keep
camcorders from twisting.
The interior ball locking of the
K-40X head has a sphere tolerance of 0.01mm, and it's equipped with an
orientation-memory locking dial. This helps yield a high load capacity
of 77 lb. The quick-release clamp features a secondary release button
that prevents any inadvertent disengagement of the camera/plate from the
clamp, thereby adding to the head's overall security and stability. The
Arca-style platform conforms to standard sizes, so you can use
compatible plates from other manufacturers.
The three control knobs allow a photographer to exercise
extremely fine control over the orientation of the camera, whether it's a
DSLR, 35mm, medium-format camera, or even a camcorder. Pan, for
instance, can be adjusted while the tilt stays locked, enabling precise
movement that's measurable – there are degree markers at the panning
base for panoramic photography.
The K-40X is CNC-machined from an aircraft-grade aluminum alloy
and anodized with an oxidation treatment that ensures a durable,