Geometric tests for the cases when brightness PA η is perpendicular to ξ. The leftmost column shows the ground truth for the cases τ=0.1, ξ=0^°, η=90^° (top) and ξ=120^° (bottom). Mean images from Comrade posteriors are shown in the middle. The rightmost column shows measured τ and ξ posteriors (68% and 95% confidence contours) compared with true values in dashed lines. The gray shaded region marks the region between τ of the groundtruth model without any convolution and with convolution of a Gaussian up to 20 μas size.