We study the effect of noise in the density field, such as would arise from a
finite number density of tracers, on reconstruction of the acoustic peak within
the context of Lagrangian perturbation theory. Reconstruction performs better
when the density field is determined from denser tracers, but the gains
saturate at n~1e-4(h/Mpc)^3. For low density tracers it is best to use a large
smoothing scale to define the shifts, but the optimum is very broad.Comment: 2 pages, 1 figure
