Scaling relations between supermassive black hole (SMBH) mass, MBH, and various host spheroid properties are a powerful tool for studying galaxy-(black hole) coevolution. Furthermore, these relations enable us to predict the masses of SMBHs in other galaxies, and to measure the SMBH mass function and quantify the SMBH space density in our local universe. Graham & Driver (2007) presented evidence for a strong correlation between MBH and the central light concentration of the host bulge, quantified by the Sérsic index n. The MBH - n relation might be one of the simplest and strongest black hole mass scaling relations, requiring only uncalibrated galaxy images. However, the recent literature has failed to recover a strong MBH - n relation. Working with the authors of those works, we have successfully recovered the useful MBH - n relation. Moreover, we have explored for potential substructure in the MBH - n diagram based on galaxy morphology (elliptical or disc) and the nature of the central light profile (Sérsic or core-Sérsic).
Future work will focus on accurately modelling the bulge/disc structure of ~80 local galaxies with direct MBH values and a re-investigation of all the black hole mass scaling relations.