  The c-axis resistivity in irradiated and in pristine BSCCO(2212) crystals is
measured as a function of the in-plane magnetic field component at fixed
out-of-plane component B_\perp in the vortex liquid phase at T=67 K. From this
data we extract the dependence of the phase difference correlation length
inside layers on B_\perp and estimate the average length of pieces of vortex
lines confined inside columnar defects as a function of the filling factor
f=B_\perp / B_\phi. The maximum length, about 15 interlayer distances, is
reached near f=0.35.
