  Recently there has been a renewed interest in the power-2 limb darkening law
for modeling exoplanet transits. This law provides a better match to the
intensities generated by spherical stellar atmosphere models than other
2-parameter laws. To help facilitate a wider use of the power-2 law we correct
a minor error and, expanding on previous work, suggest a parametrization that
can improve the sampling required by some numerical methods such as MCMC.
