  We present photometry of WASP-10 during the transit of its short-period
Jovian planet. We employed the novel PSF-shaping capabilities the OPTIC camera
mounted on the UH 2.2m telescope to achieve a photometric precision of 4.7e-4
per 1.3 min sample. With this new light curve, in conjunction with stellar
evolutionary models, we improve on existing measurements of the planetary,
stellar and orbital parameters. We find a stellar radius Rstar = 0.698 +/-
0.012 Rsun and a planetary radius Rp = 1.080 +/- 0.020 Rjup. The quoted errors
do not include any possible systematic errors in the stellar evolutionary
models. Our measurement improves the precision of the planet's radius by a
factor of 4, and revises the previous estimate downward by 16% (2.5sigma, where
sigma is the quadrature sum of the respective confidence limits). Our measured
radius of WASP-10b is consistent with previously published theoretical radii
for irradiated Jovian planets.
