  Motivated by the recent optical and photoemission measurements on
half-metallic ferromagnetic three-dimensional manganites, we combine a
tight-binding fit of the one-particle bandstructure with the dynamical
mean-field theory, which treats the dynamical orbital correlations and the
combination of Jahn-Teller and doping-induced disorder on the same footing. We
show how all of the above effects are necessary to obtain good semiquantitative
agreement with experimental features. As applications, we show how modest
external magnetic fields drive drastic changes in the optical spectrum,
demonstrating the {\it colossal ac magnetoconductivity}. The photoemission
lineshape contribution is evaluated, and good agreement with published
experimental work is found.
