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We describe the evolution of the x-ray scattering pattern which forms on an area detector when a divergent, coherent nanobeam is diffracted from a perfect or weakly deformed single crystal. We show that the scattering can be considered as virtual diffraction from an angular aperture in reciprocal space; this is analogous to pinhole diffraction in real space. We define an angular Fresnel number, YA, which allows the categorization of the nanodiffraction image into near-field, intermediate-field, and far-field regimes. We provide equations for YA in simple geometries and show that dynamical scattering artifacts are eliminated through wave interference in the far-field image; this is the only regime where direct analysis of the charge coupled device image using geometrical formulae to transform distances to diffraction angles is possible.