Ballhead Torque Calculator
Enter your camera and lens weight and the lever arm to your combined center of gravity to estimate the holding torque your ball head needs.
Torque estimate
Why a front-heavy lens is harder to hold
The required torque is simply the weight of your camera and lens, acting under gravity, multiplied by the horizontal distance from the ball head's pivot to where that weight is actually centered. Because torque scales with distance as well as weight, a long telephoto lens can demand far more holding torque than a compact prime of a similar total weight, simply because its center of gravity sits much further from the pivot.
When a rated torque figure for the head is available, the calculator flags anything above 60% of that rating as marginal and anything above the rating itself as overloaded — a margin that leaves room for the slow creep that friction locks are prone to over a long exposure or an unattended shoot.
Frequently Asked Questions
What is 'ballhead creep' and why does torque matter?
Creep is when a locked ball head slowly droops under a front-heavy lens, usually after the shot is framed and you walk away. It happens when the weight of the camera and lens exerts more rotational force (torque) than the head's friction lock can hold indefinitely. Estimating the required torque against the head's rated capacity is a quick way to check headroom before it happens mid-shoot.
How is torque calculated here?
Torque equals force times lever arm. The 'force' is the weight of your camera and lens acting under gravity, and the 'lever arm' is the horizontal distance from the ball's pivot point to the combined center of gravity of that camera and lens. A longer lens sitting further forward increases the lever arm and therefore the torque, even if the total weight stays the same.
Where do I find a lever arm figure for my setup?
It's rarely published, so the practical approach is to balance the camera on a straight edge or your finger under the lens to find its center of gravity, then measure from there back to where the lens foot or plate sits on the ball head. For a lens without a separate foot, the estimate is rougher — measure from the camera's tripod socket to roughly the midpoint of the lens.
My result says 'marginal' — what should I do?
A gimbal head or a lens with its own tripod collar and foot moves the load's center of gravity back over the head's pivot, dramatically cutting the effective lever arm and the torque required. For a fixed ball head, tightening further, using a head with a higher rated capacity, or supporting the lens separately (e.g. with a lens collar) are the usual fixes.
Educational tool only. The lever arm is rarely published and normally has to be estimated — treat the result as a planning guide, and always test a new setup's grip before leaving it unattended.