Left: Gyoto log-scale image of a BH with spin a = 0.5 and inclination i = 89°, surrounded by a thin disk with emission profile (Eq. (50)) with parameters μ = r₋, γ = −2, and σ = 1.5M. The bright horizontal line is the direct n = 0 image of the disk viewed almost edge-on. Right: zoom-in around a region with β ≈ 0. The width of the n = 1 subring for β > 0 is of the same order of magnitude as the width of the n = 2 ring for β < 0.