Bi-directional reflectance correction

Some comments on when BRDF correction should be applied are needed.

E.g. to remove hotspot (with a good example of an image that shows the hotspot).

When deriving biophysical estimates from reflectance data - especially if the view angle in the image is large, or multiple images are being used (e.g. a mosaic), or if there is sun angle variation in the data and estimates derived from the data are to be compared (e.g. images captured at different times of day, or images captured at different time of year, or images captured where the is large difference in latitude).

Attached is an example of BRDF correction of Landsat imagery for QLD - credit goes to QLD Dept of Environment and Resource Management.

Example of bi-directional correction
Top of atmosphere reflectance: caption needed.
Empirical radiometric correction: caption needed.

Reference:

Reference please.