Digitization and Resolution in 2DH before current fix
The plot below shows the x-position (upper pannel) and y-position (lower panel) of
hits found by 2DH before the fix being discussed. There is clear digitization in
both coordinates, but it is much worse in y. For reference, the red lines indicate
the size of one pad (for x plot) or one bucket (for y plot).
The next plot shows the distribution of residuals for x and y.
(The number of entries in the x-plot is lower because I had to make a cut such that |x|<1 cm.
The reason is that BTF sometimes makes xdev_fit on the order of meters!!!)