  We explore how observations relate to the physical properties of the emitting
galaxies by post-processing a pair of merging $z\sim2$ galaxies from the
cosmological, hydrodynamical simulation NewHorizon using LCARS (Light from
Cloudy Added to RAMSES) to encode the physical properties of the simulated
galaxy into H$\alpha$ emission line. By carrying out mock observations and
analysis on these data cubes we ascertain which physical properties of the
galaxy will be recoverable with the HARMONI spectrograph on the European
Extremely Large Telescope (ELT). We are able to estimate the galaxy's star
formation rate and dynamical mass to a reasonable degree of accuracy, with
values within a factor of $1.81$ and $1.38$ of the true value. The kinematic
structure of the galaxy is also recovered in mock observations. Furthermore, we
are able to recover radial profiles of the velocity dispersion and are
therefore able to calculate how the dynamical ratio varies as a function of
distance from the galaxy centre. Finally, we show that when calculated on
galaxy scales the dynamical ratio does not always provide a reliable measure of
a galaxy's stability against gravity or act as an indicator of a minor merger.
