  In the iconic measurements of atomic spin-1/2 or photon polarization, one
employs two spatially separated and noninteracting detectors. Each detector is
binary, registering the presence or absence of the atom or the photon. For
measurements on a $d$-state particle we recast the standard von Neumann
measurement formalism by replacing the familiar pointer variable with an array
of such detectors, one for each of the $d$ possible outcomes. We show that the
unitary dynamics of the premeasurement process restricts the detector outputs
to the subspace of single outcomes, so that the pointer emerges from the
apparatus. We propose a physical extension of this apparatus which replaces
each detector with an ancilla qubit coupled to a readout device. This
explicitly separates the pointer into distinct quantum and (effectively)
classical parts, and delays the quantum to classical transition. As a result,
one not only recovers the collapse scenario of an ordinary apparatus, but one
can also observe a superposition of the quantum pointer states.
