Unreferenced objects from the sky are regularly discovered by amateur astronomers from their own images or from professional images. Like the DSH list, thanks to the initiative of Agnès Acker and Pascal Le Dû [1][5], a list of planetary nebulae candidates is maintained in France and regularly published in the SAF magazine and then in VizieR. Recently, amateur astronomers specializing in spectroscopy have managed to observe the spectra of some of these candidates to confirm their nature.

The spectra of some candidates were acquired with modest instruments from 0.09 m to 0.2 m diameter. Specific missions have allowed amateur teams like the PNST to use larger telescopes from 0.5 m (AstroQueyras) to 1 m (Calern) diameter. The spectrographs used are at low resolution at F/D = 5.