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Aberration corrected electron optics allows routine acquisition of high spatial resolution spectroscopic images in the scanning transmission electron microscope, which is important when trying to understand the physics of transition-metal oxides such as manganites. The physical properties of these perovskites are intimately related to the occupancies of the partially filled $3d$ bands, which define their oxidation state. In this work, we review procedures to obtain this electronic property in ${\text{La}}_{x}{\text{Ca}}_{1\ensuremath{-}x}{\text{MnO}}_{3}$ from atomic-column-resolved electron energy-loss spectra measured in the aberration corrected scanning transmission electron microscope. In bulk samples, several features of both the average $\text{Mn}\text{ }{L}_{2,3}$ edge and the $\text{O}\text{ }K$ edge fine structure change linearly with Mn nominal valence. These linear correlations are extracted and used as a calibration to quantify oxidation states from atomic resolution spectroscopic images. In such images, the same fine-structure features exhibit further changes, commensurate with the underlying atomic lattice. Mn valence values calculated from those images show unexpected oscillations. The combination of experiment with density-functional theory and dynamical scattering simulations allows detailed interpretation of these maps, distinguishing dynamical scattering effects from actual changes in electronic properties related to the local atomic structure. Specifically, in ${\text{LaMnO}}_{3}$, the two nonequivalent O sites can be distinguished by these methods.