Shock waves of the order of hundreds of kilobars are produced in a tin foil 50 &mgr;m thick by a Nd:YAG laser system with a wavelength of 1.06 &mgr;m, pulse width of 7 ns [full width at half-maximum (FWHM)] and irradiance in the range(1.4–2.4)×1013 W/cm2,focused to a spot of 200 &mgr;m. Off-axis holographic measurements of the target, after 0.5 and 1 &mgr;s from the shock arrival, are reported. The hologram is produced by backscattering of a pulse, 6.5 ns (FWHM) of green laser light, from the ejected material from the target. ©1997 American Institute of Physics.