Inspection systems employing radiation filters with different attenuation characteristics to determine specimen irregularities, and related methods are disclosed. An inspection system includes a radiation emitter configured to emit a radiation beam along a radiation trajectory. Some of the radiation may be reflected by the specimen as backscatter and received by at least one radiation detector of the inspection system along the radiation trajectory. Irregularities and various materials of the specimen may produce backscatter radiation at different energies and/or scatter angles which may be identified by employing radiation filters having different attenuation characteristics. By employing these filters in communication with the radiation emitter and the radiation detector, the backscatter radiation passed through the filters may be measured and integrated at different positions of the radiation beam to produce a composite image of the specimen. In this manner, irregularities and associated materials within the specimen may be more easily identified.