  We study the ramification divisors of projections of a smooth projective
variety onto a linear subspace of the same dimension. We prove that the
ramification divisors vary in a maximal dimensional family for a large class of
varieties. Going further, we study the map that associates to a linear
projection its ramification divisor. We show that this map is dominant for most
(but not all!) varieties of minimal degree, using (linked) limit linear series
of higher rank. We find the degree of this map in some cases, extending the
classical appearance of Catalan numbers in the geometry of rational normal
curves, and give a geometric explanation of its fibers in terms of torsion
points of naturally occurring elliptic curves in the case of the Veronese
surface and the quartic rational surface scroll.
