Resulting translient statistic (Z ²; left panel) and proper statistic (S ²; right panel) images computed for the image pair shown in Figure 2. The red crosses mark the location of x _c ≡ ( p + q )/2, the center between the positions of the point sources in the reference and new images. In the squared translient statistic image one can see a single peak approximately centered at x _c , whereas in the squared proper statistic image two peaks on opposite sides of x _c (diagonally) can be observed. This is the typical qualitative appearance of the two detector images when the data are generated by a point source undergoing pure translation (without any flux change). S ² has units of ﹩{\left({\rm{S}}/{\rm{N}}\right)}^{2}﹩, and since σ _n = σ _r , then the S/N in the N and R images is about ﹩\sqrt{2}﹩ times higher compared to the value in the S image.