== [[span(style=color: blue, **P3.12 Distortion map** )]]== - **Phase** : 3 - **Status** : [[span(style=color: blue, **partially COMPLETE, need more data** )]] - **Category** : Nighttime testing (functionality and operability) (C5) + Nighttime calibration (C6) - **Recurrence** : once every week starting from commissioning + on request. - **Duration** : 2 hours **Description** - Determine distortion map of science frame. Monitor distortion coefficient with time (weekly calibration) and measure the precise distortion of a given observation in any setup, if requested. **Prerequisites** - Authorize SHARK-NIR on the SX side. - Atmospheric conditions: AO working conditions. - Bad pixel map, Background or Dark, Flat-field, distortion map **Procedure** - Observe a dense field (e.g., a globular cluster) with accurate HST astrometry and a guide star bright enough (mag F860W < 11). **Templates** **Success criteria** - Better than 1 mas over FoV. **Notes** - Same as activity 9.6 in AD4 **LBTO support** - AO support **Date performed and by whom**