An ultra-high-speed radiographic imaging assembly (at least 900 system speed) is useful especially for pediatric radiography to provide images with improved contrast and sharpness and reduced fog. The imaging assembly includes a symmetric film having a speed of at least 400 that includes at least two silver halide emulsion layers on each side of a film support that comprise tabular silver halide grains. The imaging assembly also includes two fluorescent intensifying screens wherein the pair of screens has a screen speed of at least 400 and the screens have an average screen sharpness measurement (SSM) value greater than reference Curve A of FIG. 4. The screens can have a support that includes a reflective substrate comprising a continuous polyester phase and microvoids containing inorganic particles dispersed within the polyester phase.