Working with real JWST NIRCam images
_uncal.fits (Level 1b) -- uncalibrated images
Stage 1: Detector1Pipeline: Count-rate slopes: Detector-level corrections and ramp fitting
_rate.fits (Level 2a) -- cosmic rays removed
Stage 2: Image2Pipeline: Calibrations: Instrument-mode: background subtraction and flat field correction
_cal.fits (Level 2b) -- galaxy wings appear
Stage 3: Combining multiple exposures within an observation
_i2d.fits (Level 2c) -- drizzled image
Issues:
- match background levels in short wavelength detectors
- 1/f noise striping
- wisps
- snowballs