Finer Local Data Without Guaranteed Dimensional Legitimacy: A Diagnostic Note on Reconstruction and Surface-Determination Dependence in XCT Metrology

This technical note examines a narrow methodological issue in dimensional X-ray computed tomography (XCT). The central point is that finer local data, smaller voxels, or more stable subvoxel surface extraction do not by themselves guarantee dimensional legitimacy or inter-procedural comparability when the final result remains sensitive to reconstruction and surface-determination choices. The note does not argue that XCT is unreliable or non-metrological. Its claim is narrower and diagnostic: in an indirect metrological pipeline, local refinement is not by itself sufficient to secure a uniquely robust dimensional result. The discussion is framed in relation to measurement models, traceability, procedural dependence, and comparability in XCT dimensional metrology.