Beyond the visible canopy

This is a picture taken with an old Nikon Coolpix 990, with its original built-in filter blocking near infra-red radiation removed and an extra cold mirror filter, blocking most of the visible light. A fish-eye lens has been used to get hemispherical pictures of forest canopies for forest structure analyses. The image points upwards to a Scots pine canopy in the Prades Mountains (Catalonia, NE Spain), affected by drought-induced mortality.