  Dynamically different groups of comets and active asteroids with orbits at 2
- 5 a. u. show dust activity in varying degrees and forms. Photometric study
and comparison of physical parameters can help to classify mechanisms and
nature of the activity for such objects. We present new observations using
broadband photometry of 15 active objects in the main asteroid belt and
surrounding regions obtained during 2012 - 2016. The study aims to compare the
physical properties of main-belt comets (MBCs), quasi-Hilda comets (QHCs), and
active asteroids (AAs). The observations were carried out with the 0.7-m
telescope of the Kyiv Comet Station, Ukraine, and with the 1.23-m telescope at
the Calar Alto Observatory, Spain, using BVR broadband filters. Upper limits
for the nuclear radii, Afrho parameters, and color indices were measured. The
results of 2012 - 2016 observations suggest that there exist systematic
differences in the physical parameters of MBCs and QHCs.
