Photometric systems

For broadband systems, the most common is the UBVRI system, originally established by Johnson in the 1960s. However, even the UBVRI system has undergone some revisions, and Johnson's original system is not quite the one used predominantly today.

UBVRI. Cousins RI. Subtleties of Johnson vs. Cousins vs. Landolt.

Gunn system, uvgriz.

HST system.

Sloan system.

Choice of photometric system for studies of stars: determination of temperatures, reddenings, surface gravities, metallicites.

Medium band: Stromgren system, uvby$\beta$. Others: DDO, Washington.