Method of measuring, device manufacturing method, metrology apparatus, and lithographic system

A metrology apparatus for measuring a plurality of structures on a substrate, the metrology apparatus comprising:

• a first measurement system configured to perform a first measurement process, the first measurement process comprising individually measuring each of the plurality of structures to measure a first property of the structure;
• a second measurement system configured to perform a second measurement process, the second measurement process comprising measuring a second property of each of the plurality of structures;
• and
• a control system configured to control the second measurement process such that a radiation property of radiation used to illuminate each structure during the second measurement process is individually selected for that structure using the measured first property for the structure.