Minimize Level-1B

SLSTR Level-1 processing is divided into three different modes:

  • calibration processing mode
  • observation processing mode
  • joint mode.

The SLSTR Level-1B product is generated during observation and joint processing mode.

The SLSTR Level-1B product gathers, for each view and for each channel, the full-resolution geolocated radiometric measurements.

For thermal IR and fire channels (labelled as S7 to S9 and F1, F2 for fire channels), the radiometric measurements are expressed in Top Of Atmosphere (TOA) brightness temperatures. In the case of visible / NIR / SWIR channels (labelled as S1 to S6 channels), these measurements are expressed in TOA radiances.

The radiometric measurements are indexed according to the across track and along track direction:

  • on a 1 km grid for brightness temperature
  • on a 0.5 km grid for radiances. In this case, three stripes are distinguished: A, B and TDI, with TDI a derived product from A and B stripes. Only the stripes selected in the processing configuration file are available.

The SLSTR Level-1B product also contains:

  • quality flags concerning cloud flagging and scan and flip mirror testing
  • surface pixel classification information
  • meteorological annotations
  • quality annotations, such as estimates of detector noise measured at VISCAL or black bodies
  • in the frame of coming evolutions, one file gathering parameters computed during stray light correction could be added
  • arrays of indices to retrieve the position of each pixel in the instrument measurement frame
  • cartesian and geodetic coordinates associated with the radiometric measurements and to the tie-points grid defined for SLSTR.