== P3.7	Internal TT loop working and performance== 
 
- **Phase**		:	3  
- **Status**		: 	Draft	 
- **Category**	: 	Nighttime testing (functionality and operability) (C5) + Nighttime testing for performance (C7)
- **Recurrence**	: 	once at commissioning
- **Duration**	: 	3 hours

**Description**
- Evaluate the performance of the internal tip-tilt (TT) loop of SHARK-NIR for stars of varying brightness.

**Prerequisites**
- Atmospheric conditions: TBD
- Authorize SHARK-NIR on the SX side.
- Stars (of known brightness from 8mag-13mag in the R band) as targets.
- AO is working.

**Procedure**
- Run the internal TT loop after the star is acquired and the AO loop is closed. 
- Take unsaturated images of the star for a given (?) science filter before and after the internal TT loop closure in the SCICAM.
- Take data in TECCAM simultaneously. 
- Use data to estimate the improvement of the residual jitter after the TT loop is closed.
- Repeat for different star magnitudes.
- should we perform as a function of elevation as well? We can choose stars accordingly, then?

**Templates**
- SHARKNIR_gen_tiptilt_loop (not released)

**Success criteria**
- Estimate the residual jitter after SOUL-AO is closed for a given seeing and star brightness.
- Checking the working and performance of the internal TT loop.
- Quantify and numbers to add?

**Notes**

**LBTO support**
- AO support

**Date performed and by whom**