Both proton auroral and downward flowing ion events have significant fast ion components. For these phenomena we demonstrate that charge exchange and collisional ionization processes can exert a strong effect on the imaging of ionized density structure to the lower ionosphere. This has value in relating ionized density spectral measurements at altitudes of the F region maximum and below to plasma behavior at higher altitudes, as well as providing initial conditions for locally driven plasma instabilities. It is shown that charge exchange of fast ions into fast neutrals results in the rapid attenuation of structure with neutral mean free paths much larger than the structure dimensions and the generation of structure of larger size. For structure with dimensions much larger than the neutral mean free path, fast neutral loss is diffuse rather than convective and attenuation of structure is less rapid.