Detection efficiency ϵ(m_0i) on D1 derived from Monte Carlo images as a function of the generated magnitude m_0i at maximum light. Blue diamonds illustrate the efficiency for the first season of data (averaged over the full mosaic excluding CCD 3), red disks are for the second season (full mosaic), open black circles are for the third season (full mosaic), and pink triangles are for the supernovae occurring during the first season on CCD 3.