  Digital Access to a Sky Century @ Harvard (DASCH) is a project to digitize
the collection of ~500,000 glass photographic plates held at Harvard College
Observatory. The collection spans the time period from 1880 to 1985, during
which time every point on the sky has been observed approximately 500 to 1000
times.
  In this paper we describe the results of the DASCH commissioning run, during
which we developed the data-reduction pipeline and fine-tuned the digitzer's
performance and operation. This initial run consisted of 500 plates taken from
a variety of different plate-series, all containing the open cluster Praeseppe
(M44). We report that accurate photometry at the 0.1mag level is possible on
the majority of plates, and demonstrate century-long light-curves of various
types of variable stars in and around M44.
