Minimize Mis-registration

The inter-channel spatial mis-registration information is represented as correspondence grids between the OLCI reference channel and other OLCI and SLSTR near-nadir channels.

These grids are computed by SYNERGY Level-1 processing. For each channel the mis-registration grid is stored in a dedicated netCDF file.

  • OLCI channels mis-registration data files
There is one data file for each OLCI channel. Each correspondence grid between the OLCI reference channel camera modules and channel Oai is represented by three 3D variables: L1b_row, L1b_col and L1b_removed of size [N_CAM, N_LINE_OLC, N_DET_CAM].

Let fl1b = L1b_row (m, k, j) and jl1b = L1b_col (m, k, j) then (fl1b, jl1b) is the Level-1B image pixel location in channel Oai of OLCI camera module m corresponding to pixel (k,j) in OLCI reference channel of camera module m.

The same correspondence is defined for removed pixels

  • SLSTR channels mis-registration data files for nadir view
There is one data file for each SLSTR nadir view channel for which computation has been enabled by the user (i.e. solar channels are always presents, thermal and fire channels are optional). Each correspondence grid between the OLCI reference channel camera modules and channel Si is represented by three 3D variables: L1b_row, L1b_col and L1b_orphan of size [N_CAM, N_LINE_OLC, N_DET_CAM]. Let il1b = L1b_row (m, k, j) and jl1b = L1b_col (m, k, j) then (il1b, jl1b) is the L1b image pixel location in channel Si of SLSTR nadir view corresponding to pixel (k,j) in OLCI reference channel of camera module m. The same correspondence is defined for orphan pixels.
  • SLSTR oblique view collocation data files
These files are present only if the computation of oblique views is enabled in the SYNERGY Level-1 processing. In this case, the number of data files in the product depends on the SWIR sub-bands ("A", "B" or "TDI") included in the Level-1 product. The file for the "A" sub-band is always present. Files associated with 1km channels are present if the computation of thermal/fire channels is enabled. If the computer of "B" or "TDI" SWIR sub-band is enabled in SYNERGY Level-1 processing, then corresponding collocation files must be added accordingly. Each correspondence grid between the OLCI reference channel camera modules and SLSTR sub-bands is represented by three 3D variables: L1b_row, L1b_col and L1b_orhphan of size [N_CAM, N_LINE_OLC, N_DET_CAM]. Let il1b = L1b_row (m, k, j) and jl1b = L1b_col (m, k, j) then (il1b, jl1b) is the L1b image pixel location in the SLSTR oblique view considered stripe corresponding to pixel (k,j) in OLCI reference channel of camera module m. The same correspondence is defined for orphan pixels.