== P3.29	Distortion map == 
•	**Phase**		:	3  
•	**Status**		: 	Draft	 
•	**Category**		: 	Nighttime calibration (C5)
•	**Recurrence**	: 	once every week starting from commissioning + on request.
•	**Duration**		: 	10 minutes
**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).
**Success criteria**
•	Better than 1 mas over FoV. 
**Notes**
•	Same as activity 9.6 in AD4
**LBTO support**
•	Support from LBTI/LBTO?
**Associated SHARK-NIR personnel**
•	JF, LM, MdP
**Date performed and by whom**