J-PLUS (r − J0660) vs. (r −i) colour–colour diagram with the objects selected from J-PLUS DR1. The blue circle represents the PN candidate with ID 26063-6129, the green circle is the known PN Sp 4-1, the red diamonds are the H II galaxies LEDA 2790884 and LEDA 101538. The matches of the J-PLUS and S-PLUS data with the HASH catalogue are also presented in the diagrams. In agreement with the classification of HASH PN database. The purple circle is the true PN (tHASH PN) Jacoby 1, the brown circle is the likely PN (lHASH PN) TK 1 and the orange circles represent the possible PNe (pHASH PN) Kn J1857.7+3931, and KnPa J1848.6+4151. These objects were observed by J-PLUS. The pHASH PN Fr 2-21 is indicated by the magenta circle. This source was found in S-PLUS DR1. See text for further details. The error bars are smaller than the symbols.