1.1 ,These reference radiographs illustrate various categories, types, and severity levels of discontinuities occurring in high-strength copper-base, nickel-copper, and related alloy castings. The reference radiograph films are an adjunct to this document and must be purchased separately from ASTM International, if needed (see 2.3). Categories and severity levels for each discontinuity type represented by these reference radiographs are described in 1.2.