  The Quintuplet and Arches clusters, which were formed in the harsh
environment of the Galactic Center (GC) a few million years ago, have been
excellent targets for studying the effects of a star-forming environment on the
initial mass function (IMF). In order to estimate the shape of the low-end IMF
of the Arches cluster, Shin & Kim devised a novel photometric method that
utilizes pixel intensity histograms (PIHs) of the observed images. Here, we
apply the PIH method to the Quintuplet cluster and estimate the shape of its
low-end IMF below the magnitude of completeness limit as set by conventional
photometry. We found that the low-end IMF of the Quintuplet is consistent with
that found for the Arches cluster--Kroupa MF, with a significant number of
low-mass stars below 1 $M_{\odot}$. We conclude that the most likely IMFs of
the Quintuplet and the Arches clusters are not too different from the IMFs
found in the Galactic disc. We also find that the observed PIHs and stellar
number density profiles of both clusters are best reproduced when the clusters
are assumed to be at three-dimensional distances of approximately 100 pc from
the GC.
