PV planes for RA and Dec showing the fluxes of Hα+[NII], [OII], Hβ, the U emission, [OII], NII, HeI, and [NII]. In each plane, the horizontal dashed lines indicate velocities in steps of ±500 km s⁻¹ with respect to the rest line (solid line), while the positions of the stars near V1425 Aql are marked with vertical dashed white lines. In the RA planes east is to the left, while in the Dec planes north is to the right. To highlight the flux from the nova shell, the planes have been smoothed and the pixels with low fluxes have been discarded. In all cases, the fluxes are presented using a linear scale. All observed lines trace the inner shell, which appears as a compact, symmetric, and slow component (υ_exp ≲500 km s⁻¹). The outer shell appears clearly in the [OIII] planes as an asymmetric component, but also in [NII] as a little horn in the red part of the Hα+[NII] planes.