Likelihoods (normalised to their maximum) of the confusion at 1 mm, 2 mm, and the cross-confusion 1 × 2 mm for different subsets of our data. The central points and their 1-σ equivalent error bars are shown for convenience and have arbitrary ordinates. ‘Half 1’ refers to scans oriented at 40°. ‘Half 2’ refers to scans oriented at −50°. ‘All’ refers to the total sum of the two.