Best-fit galaxy template in observed wavelengths from LePhare including the emission line contribution. Twelve filters were used to estimate these photometric redshift. The filled squares represent the ISOCOR magnitudes of our object, and the empty circles show the magnitudes from the best model. The downward facing triangles represent the detection limit used for the photometric redshift estimation. Top: for the complete nebula, magnitude of aperture 35 pixels. Centre: for the bright core, with 3 arcsec aperture, 3sigma detection. Bottom: for the faint halo with 15 pixels aperture. The three fits give a redshift of around 3.3 ± 0.05.