The second and third aircraft are rather Nieuport 24bis than Nieuport 17s. The latter had a rectangular cross-section of a fuselage. Airplanes visible on the picture have rounded fuselages. Besides, Ni 17s were withdrawn from the front line in mid-1917, while the picture was taken on 27th December 1917.
Source: Nieuport Aircraft of WW I by Ray Sanger and Nieuport Fighters by J.M. Bruce