1. A method of determining color parameter values, comprising: obtaining a plurality of illuminant sensor outputs, each illuminant sensor output obtained by illuminating a target at an operating temperature; obtaining a measurement of the operating temperature; retrieving model information from a reference database based on the operating temperature and the sensor outputs, the reference database containing different model information for different temperatures; determining a model for the operating temperature and the sensor outputs based on the retrieved model information; and determining color parameter values based on the determined model.