Alignment fixture for image quality test target

This invention relates in general to storage phosphor based computed radiography and more particularly to a fixture for aligning an image quality test target with storage phosphors of different sizes. A storage phosphor based computed radiography system apparatus for aligning a test target with storage phosphor assemblies of different sizes comprising; a rectangular tray for selectively holding at least a first storage phosphor assembly having a first rectangular size and a second storage phosphor assembly having a second rectangular size smaller than said first rectangular size; said tray having first and second nested receptacles for selectively holding said first or said second storage phosphor assembly and wherein said first receptacle is sized to hold a test target of said first rectangular size in alignment with a held storage phosphor assembly.