Approximate scaled top view representation of the binary system DF Cyg. The orbit of the primary star is shown as the blue ellipse. The position of the primary star at the start and end of obscuration is shown as red filled circles at positions A and B, respectively. The periastron passage is marked with a star (⋆) labelled P, the inferior conjunction as a cross (×) symbol, and the centre of mass of the binary system (and of the disc) is marked with a plus (+) symbol. The line of nodes is represented by the line N₁, N₂ and the major axis of the orbit is represented by the line M₁, M₂. The longitude of periastron, ω, has a value of 183° as obtained from the orbital fit. The grey shaded region represents the circumbinary disc.