Solar radiation enters the Earth's atmosphere with a portion being scattered by clouds and aerosols.

Processing, archiving and distributing Earth science data
at the NASA Langley Research Center

Why do I sometimes see bright speckles in an image of the Terrain product, particularly at the oblique camera angles?

MISR Level 1B2 data products use various high data values to signify fill, and one of the fill values (16377) in the 14 MSB's of the scaled radiances signifies that this location on the SOM grid was obscured from the camera's view by intervening topography. Because greater amounts of topographic obscuration occur at the more oblique angles, the prevalence of this particular fill value increases as the view angle increases. This particular fill value does not apply to the Ellipsoid product, because for each sample, whatever radiance was observed along the line of sight is projected to the ellipsoid grid location.