Chapter 3: WFC3 Data Calibration 3.1 Calibration Overview 3.1.1 Image Processing Summary 3.2 Overview of calwf3 3.2.1 Structure and Processing Flow 3.2.2 UVIS Processing 3.2.3 IR Processing 3.2.4 Running calwf3 3.3 Keyword Usage 3.4 Description of Calibration Steps 3.4.1 wf3ccd 3.4.2 wf32d 3.4.3 wf3ir 3.4.4 wf3rej 3.5 Calibration of WFC3 Spectroscopic Data 3.6 When should I recalibrate my data? 3.7 Manual Recalibration of WFC3 Data 3.7.1 Requirements for Manual Recalibration 3.7.2 calwf3 Examples