GRISMS FOCUS
The collimator is in simulation (i.e. it is not moving when given a coomand by the software), at the optimal position for both imaging and spectroscopy! Ignore the numbers given bellow. This page is being kept for historical reasons.
The optimal focus for the grisms is determined by using the JG mask. I.e., the focus is determined for the best spatial resolution. In general, the position of the collimator required to obtain the best spectral resolution is different from the collimator position required for the best spatial resolution.
| Date\Grism | Blue Grism | Red Grism | HR Z | HR J | HR H | HR Ks |
| 1998-05-17 | 2000 | 0 | ||||
| 1999-01-22 | -1567 | 541 | 1294 | 2016 | 3924 | 5607 |
WOLLASTON FOCUS
| Date\Filter | Wollaston Lower (Ks) | Wollaston Upper (Ks) |
| 1998-06-30 | 3883 | 2976 |