== [[span(style=color: green, **SDC2	Instrument flat field, detector linearity and bad pixels** )]] ==

- **Phase**		:	1  
- **Status**		: 	[[span(style=color: green, **COMPLETE** )]] 
- **Category**	: 	Daytime calibration (C3)
- **Recurrence**	: 	every day, with setup on request.
- **Duration**	: 	20 minutes per configuration  (this duration is valid only during regular operations, i.e., after commissioning)

**Description**
- Instrument flat field, detector linearity, and bad pixels. 

**Prerequisites**

**Procedure**
- Use the calibration flat-field source.
- This calibration is performed illuminating the detector uniformly using the instrument FF lamp, for each filter. 
- It is expected that the detector FF depends on filters, the final accumulated charge in the pixels. Thus, a series of exposures will be taken at different count levels (realized via ND filters and/or DIT) for each filter setup. In this case, the template takes the background frames automatically. Comparing different count rates at constant DIT will also yield a linearity map of the detector. 

**Templates**
- SHARKNIR_gen_cal_InstrumentFlatField

**Success criteria**
- 95% luminous uniformity at a large scale.
- 99% luminous uniformity at pixel-to-pixel scale 10-2.
- Large scales filtered out, only a small detector scale will remain. Effect of the large-scale flat field on DBI (rescaling in flux & wavelength) has negligible impact on DBI performances.

**Notes**
- Same as activity 7.9 in AD4

**LBTO support**

**Date performed and by whom**