In C-arm systems, the X-ray beam output is determined by both the signal returned from the automatic exposure device (AED) in the receptor and the exposure table set up for the exam type. The settings for the exposure (as well as aspects of the image receptor and display) will affect the qualities or resolutions of the resulting image. This chapter covers the factors and qualities of images produced by an X-ray C-arm system, and the effect that varying exposure factors has on the resulting image quality and resolutions. This includes spatial, temporal, and contrast resolutions, as well as the effects of under- and overexposure, and distortion or artefacts on the produced images.