  New photometry of RRab and RRc stars in Omega Cen is used to calibrate their
absolute magnitudes M_V as a function of: a) metallicity; and b) the Fourier
parameters of light curves in the V band. The zero point of both calibrations
relies on the distance modulus to the cluster derived earlier by the CASE
project based on observations of the detached eclipsing binary OGLE GC17. For
RRab variables we obtained a relation of M_V=(0.26\pm 0.08)[Fe/H]+(0.91\pm
0.13). A dereddened distance modulus to the LMC based on that formula is
$\mu_{0}=18.56\pm 0.14$ mag. The second calibration of M_V, which is based on
Fourier coefficients of decomposed light curves, results in the LMC distance of
$\mu_{0}=18.51\pm 0.07$ mag.
