Simon
Below you can find the first results of Yesterday's measurement with an S-polarized input beam. The structure of the map is quite similar to the wavefront-error measurements done by Hirose-san last year(?).
The homogeneity in terms of the polarization angle is ~2 degrees which is almost twice as much as for ETMX. However, also this is apparently consistent with Hirose-san's measurements.
The view onto the map is as the incoming beam would "see" the substrate.