We present wide-field and high-precision BV and Ca and Stroemgren by photometry of {omega} Centauri, which represents one of the most extensive photometric surveys to date for this cluster. The member stars of {omega} Cen are well discriminated from foreground Galactic field stars in the hk[=(Ca-b)-(b-y)] versus b-y diagram. The resulting "cleaned" color-magnitude diagram (CMD) has allowed us to obtain an accurate distribution of the red horizontal-branch (HB) and the asymptotic giant branch stars.