Jenne, Sheila, Stefan

We used two independent methods to verify that the beam spot positions do not move during the power increase:

Jenne and Sheila put dither lines on all optics. While they have not calibrated the output, the result is that during the power increase they did not observe any motion of the beam, but during the soft offset adjustment just afterwards they did see the spots move.

I used Kiwamu's cameras to make time lapse movies of the power-up (the first two gifs). No spot motion is observed. I also atteched two movies (gif 3 and 4) of the motion during the soft offset adjustment. The spots can be seen wiggling.

FInally, I attached a Striptool chart of the beam positions during power-up. The power increase starts at -30 minutes, and finishes at -22minutes. Then the soft loops start moving until about -16 minutes. At -12 minutes Jenne took the soft offsets out again.