Parallax effects in binary microlensing events

We demonstrate that photometric data from 1-m-class ground-based telescopes can be sufficient to observe parallax effects in Galactic microlensing events where the lens is a binary. This is a consequence of the very steep light curve which is produced when a source crosses a simple `fold' caustic. Such parallax measurements can distinguish between binary lenses located in the Galactic bulge and those in the disc.