Primary amplification peak of a static source. FGR bolometric amplification compared with the WDL approximation and the FGR approximation. The vertical dashed line at R_e = 200M divides the extreme lensing region where an FGR approach must be used from the region, where WDL approximation works. The vertical arrows denote R_ws(ψ), the radius of transitions from the strong lensing regime to the weak lensing regime for angular separations ψ = 10⁻² and ψ = 10⁻⁴. Top: first direct image. Bottom: first indirect image.