  Distance relations in a locally inhomogeneous universe are expected to behave
like the Dyer-Roeder solution on small angular scales and the
Friedmann-Robertson-Walker solution on large angular scales. Within a simple
compact clump model the transition between these asymptotic behaviors is
demonstrated and quantified. The redshift dependent transition scale is of
order a few arcseconds; this implies it should have little influence on large
angular scale cosmological tests such as the volume-redshift relation but
possibly significant effects on arcsecond angular diameter measurements of
radio galaxies and AGNs. For example, at $z=2$ on arcsecond scales a clumpy
flat universe mimics the angular diameter distance of a smooth $\Omega=0.27$
model.
