Chris and I were looking at the TF from ISI to OPLEV tonight and as part of that we imrpoved the diagnolization of the OPLEV, the axis was about 3 degrees off

The old matrix was +/-1s the new one is

 -0.9565    0.9565   -1.0417    1.0417
    1.0417   -1.0417   -0.9565    0.9565  (shown in figure)

  we got about a factor of 10 improvement (blue vs orange line)

   there is room for further improvement if needed