Fig. 2.

MPW image nomenclature. Red pips and text indicate real object whereas blue pips indicate reflections. Perspective (A, B) and top (C, D) view of MPW reflections for optically centred (A, C) and eccentric (B, D) specimen. α – primary image, β – bottom reflection, γ, δ – first set of opposing mirrors, ε, φ – second set of opposing mirrors (β images are obscured in C and D by α image). Secondary reflections such as a gamma-mirror image of a beta mirror image are denoted by mirror labels (γ-β), or an epsilon mirror image of a gamma (ε-γ), and similarly for tertiary reflections. Scale bar: 10 μm.