  We recalculate the first analytic correction beyond PFA for a sphere in front
of a plane for a scalar field and for the electromagnetic field. We use the
method of Bordag and Nikolaev [J.Phys.A, {\bf 41} (2008) p.164002]. We confirm
their result for Dirichlet boundary conditions whereas we find a different one
for Robin, Neumann and conductor boundary conditions. The difference can be
traced back to a sign error. As a result, the corrections depend on the Robin
parameter. Agreement is found with a very recent method of derivative
expansion.
