The light emissions from a magnetically filtered vacuum cathodic are are investigated using an optical multichannel analyzer. In principle, a curved magnetic solenoid prevents the neutral species produced in the vicinity of the cathode from arriving at the film deposition area. This is demonstrated in this work from the spectra obtained near the substrate in which no neutral emissions could be found. The emission spectra of copper, aluminum, and titanium vacuum arcs in H-2, He, N-2, and Ar ambient gases are studied, It is found that the ambient gases enhance the ion emissions with the exception of hydrogen, and the relative enhancement effect is greater fdr gases with larger cross sections for ionization by electron impact, When a substrate is introduced, neutral emission is observed resulting from sputtering of the deposited film by the energetic ions. Ambient gas reduces this neutral emission, while applying a negative substrate bias increases it.