  We calculate supersymmetric Wilson loops on the ellipsoid for a large class
of $\mathcal{N}=2$ SCFT using the localization formula of Hama and Hosomichi.
From them we extract the radiation emitted by an accelerating heavy probe quark
as well as the entanglement entropy following the recent works of
Lewkowycz-Maldacena and Fiol-Gerchkovitz-Komargodski. Comparing our results
with the $\mathcal{N}=4$ SYM ones, we obtain interpolating functions $f(g^2)$
such that a given $\mathcal{N}=2$ SCFT observable is obtained by replacing in
the corresponding $\mathcal{N}=4$ SYM result the coupling constant by $f(g^2)$.
These "exact effective couplings" encode the finite, relative renormalization
between the $\mathcal{N}=2$ and the $\mathcal{N}=4$ gluon propagator, they
interpolate between the weak and the strong coupling. We discuss the range of
their applicability.
