  Based on the recent advancements in the numerical simulations of galaxy
formation, we anticipate the achievement of realistic models of galaxies in the
near future. Morphology is the most basic and fundamental property of galaxies,
yet observations and simulations still use different methods to determine
galaxy morphology, making it difficult to compare them. We hereby perform a
test on the recent NewHorizon simulation which has spatial and mass resolutions
that are remarkably high for a large-volume simulation, to resolve the
situation. We generate mock images for the simulated galaxies using SKIRT that
calculates complex radiative transfer processes in each galaxy. We measure
morphological indicators using photometric and spectroscopic methods following
observer's techniques. We also measure the kinematic disk-to-total ratios using
the Gaussian mixture model and assume that they represent the true structural
composition of galaxies. We found that spectroscopic indicators such as
$V/{\sigma}$ and ${\lambda}_{R}$ closely trace the kinematic disk-to-total
ratios. In contrast, photometric disk-to-total ratios based on the radial
profile fitting method often fail to recover the true kinematic structure of
galaxies, especially for small galaxies. We provide translating equations
between various morphological indicators.
