The SVO Filter Profile Service

During the last years, and with the advent of several important photometric surveys, many astronomical studies are taking an increasingly multi-wavelength approach. But to combine photometric data coming from different sources it is necessary that these measurements are described and characterized in sufficient detail to allow for the conversion to compatible flux density and spectral energy units. In the Spanish Virtual Observatory we maintain the "Filter Profile Service"), that provides standardized information, including transmission curves and calibration, about more than 6100 astronomical filters. The service is designed to be compliant to the Virtual Observatory Photometry Data Model and all the information is provided both as a web portal and VO services so that other services and applications can access the relevant properties of a filter in a simple way.