TABLE 3.

Comparison of different approaches to measure basic phenological parameters.

	Close range mobile systems	UAVs	Field PhenoCam	Close range PhenoCams
Cost	−−	0	++	−
Set up effort	−−	−	+	−
Operational effort	−−	−	++	++
Spatial resolution	++	+	−−	++
Realistic temporal resolution	0	+	++	++

+ and ++, advantages; − and −−, disadvantages.