The definition of the value for Residual in the Reconstruction pane has changed to become more consistent with the intuition about what a residual is. The value used to represent the *diameter* of a sphere that would contain the rays contributing to a marker. It is now defined as the *radius* of that sphere, so values for Residual in Motive 1.8 should typically be set to half of what they were in previous versions of Motive.