The finite source is not an arbitrary coordinate box. It contains every E8 lattice vector up to the selected quadratic norm, so the bound preserves complete symmetry orbits. Each vector is accepted only when its exact internal coordinate lies in the canonical 720-vertex window.
The physical four-space has coordinates f₁,…,f₄. The controls select an exact value of f₄ already present in the bounded model set; no thickness or floating tolerance is used. Elser and Sloane identify an A₅ subgroup fixing f₄, so each constant-f₄ section has icosahedral symmetry. The finite norm bound clips its radial extent but not its ambient symmetry orbits.
The exact E8 automorphism acts by φ in physical space and by 1−φ internally. Amber points are members of that integer-coordinate image which remain visible inside the current finite bound. The right view carries the same edges and lattice identities into the acceptance window; its guided motion changes only how that four-dimensional internal data is projected for display.
The canonical window origin preserves the section's icosahedral symmetry and its inflation inclusion, but it is singular. The regular preset applies an exact eleventh-unit internal shift chosen to avoid every one of the 1,200 facets. It demonstrates a nearby phason pattern without boundary choices; the symmetry and same-origin inflation highlight are disabled because the translated window no longer has those centered invariants.