EMIR was shipped to the GTC on May 2016 and had its first light on June 2016. After a short and intense commissioning period, a Scientific Verification phase took place in the first half of 2017 and the instrument began its routinely operation at the GTC by the end of that year. Since the beginning, the EMIR performances have been severely hampered

We present preliminary results based on a homogeneous analysis of the DEep Spectra of Ionized REgions Database (DESIRED), a compilation of high signal-to-noise ratio optical spectra of photoionized nebulae. The database comprises more than 1800 spectra of Galactic and extragalactic H II regions and H II galaxies, and more than 200 spectra of

The completeness of stellar spectral libraries across all evolutionary phases, parameter space and chemical abundances, is essential to build more sophisticated stellar population synthesis models to decode information from galaxy spectra. On the one hand, due to distinct nucleosynthesis channels, the comparison between magnesium and calcium can