Compiled by Q.-Tuan Luong for the Large Format Page
Yaw is the sideways tilting of a standard when swing is applied to the standard after it has been tilted. This results in standards which are not parallel in any axis. Multiple adjustments are then needed to focus when two or more adjustments are made to the same standard. A yaw-free design allows the photographer to tilt and swing a standard without having the second adjustment negate the benefits of the first.
In practice, the majority of cameras are actually not yaw-free, but this does not seem to matter to users. The only application where this is critical is table-top studio situations.
The reason that a camera has yaw is the order of the movements on the camera. If the tilt is above the swing point the camera will yaw. If the tilt is below the swing point the camera will not yaw. If the swing and tilt are at the same point the camera will not yaw. By turning a yaw prone camera on the side the swing point turns into the tilt point and the camera becomes yaw free. It does this because when it was in the upright position the swing point was below the tilt point. Most yaw free cameras have 3 movement points. 1: a base tilt to set the standards parallel to the subject. 2: a swing point 3: a tilt point for Scheimpflug control. "Bob Salomon"
It is SIMPLE: "Yaw occurs, when the swing axes are not vertical" (More complicated: "Yaw occurs, when the swing axes cannot be adjusted parallel to those lines of the subject, which should appear parallel on the film". This includes above definition.) "P.Groepper" As long as you can keep your standards vertically parallel to each other, you are yaw free. You can create yaw in a yaw free camera by simply tilting one of the standards out of parallel. But you can't uncreate yaw in a yaw prone camera (except by tilting the entire camera 90 degrees to the left or right. In which case I hope you are using a heavy duty tripod and head.) I bought a Canham DLC for landscape and general outdoor shooting. It ain't yaw-free, but then I very, very,very rarely need to do the combination of inclined plane+ parallel displacement of standards+swing movements that yaw free cameras are designed for. That is usually a studio still life type of move, and one of the three reasons why I bought an ARCA F-line in the first place. That and having rise in the focus plane. Ellis Vener firstname.lastname@example.org
View or add comments