4SM things we know

Optical calibration, bathymetry, water column correction and bottom typing of shallow marine areas, using passive remote sensing imageries

4SM

Things we know

Things we don't

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Lsw

The problem with Lsw in an 8 bits image

TrustWorthy

	BPL	The Brightest Pixels Line assumption is mostly trustworthy 1 2 3
	Jerlov	Jerlov's table of diffuse attenuation coefficients for downwelling irradiance is applicable to two-ways shallow water RS radiance 1
	Deglint	Deglinting does a good job indeed! It does remove sun/sky glint - and/or some adjacency effect situations
	Panchro	The panchromatic band of SPOT XS+P may be used as an extra multispectral band (see BoraBora Sanaa 4SM_panchro)
	Smoothing	Smart Smoothing does a good job!
	Soil Line	The Soils Line is trustworthy, to a limited extent though: the RLBgb trick can help a lot!

Bandset: wavelengths in nanometers

	SPOT XS	-WL650/750/850
	Landsat TM	-WLM518.0/610.0/693.0/905.0 -WLm452.0/529.0/624.0/776.0 -cWL00.500/0.530/0.500/0.500 -WL00485.0/571.92/658.5/840.5
	Landsat ETM	-WLM513.9/600.7/692.0/898.0 -WLm441.3/519.4/630.6/771.6 -cWL??? -WL???
	IKONOS	-WLM515.9/595.5/697.7/852.7 -WLm444.5/506.4/31.8/757.3 -cWL??? -WL???
	QUICKBIRD	-WLM??? -WLm??? -cWL??? -WL???
	WV2	-WLM/453.0/508.0/581.0/627.0/689.0/744.0/890.0/954.0 -WLm/401.0/447.0/511.0/588.0/629.0/704.0/772.0/862.0 -cWL??? -WL???
	CASI	Wavelengths at mid waveband are applicable, with some caution though in the yellow-orange region of the solar spectrum. Using the -CP argument is a must.