This paper investigates the optical appearance of black holes surrounded by dark matter halos, focusing on how the presence of dark matter affects the observed images of black holes. The study considers a spherically symmetric black hole geometry, which is surrounded by a dark matter halo and an accretion disk. The dark matter halo is modeled using a Hernquist-type density distribution, and the spacetime is described by a solution to Einstein's equations coupled to an anisotropic fluid. The black hole geometry and dark matter halo together form a solution that is analyzed for its optical properties. The study compares the optical appearance of this geometry with that of a Schwarzschild black hole, focusing on the photon ring and the central brightness depression. The results show that the presence of the dark matter halo leads to minor modifications in the primary and secondary tracks of isotropic orbiting sources, as well as in the width, location, and relative luminosity of the photon rings. These modifications are small enough that they may not be distinguishable from the Schwarzschild case using current observations from very-long baseline interferometry. The paper also analyzes the effects of dark matter on the accretion disk, considering both isotropically emitting light sources and geometrically and optically thin accretion disks. The results show that the presence of dark matter can significantly affect the observed properties of the black hole shadow and the photon rings, particularly in high-compactness configurations. The study finds that the critical impact parameter for the photon sphere is modified, while the horizon radius remains unchanged. These findings suggest that the optical appearance of black holes in dark matter halos can be significantly different from that of isolated black holes, and that future observations may help distinguish between these geometries.This paper investigates the optical appearance of black holes surrounded by dark matter halos, focusing on how the presence of dark matter affects the observed images of black holes. The study considers a spherically symmetric black hole geometry, which is surrounded by a dark matter halo and an accretion disk. The dark matter halo is modeled using a Hernquist-type density distribution, and the spacetime is described by a solution to Einstein's equations coupled to an anisotropic fluid. The black hole geometry and dark matter halo together form a solution that is analyzed for its optical properties. The study compares the optical appearance of this geometry with that of a Schwarzschild black hole, focusing on the photon ring and the central brightness depression. The results show that the presence of the dark matter halo leads to minor modifications in the primary and secondary tracks of isotropic orbiting sources, as well as in the width, location, and relative luminosity of the photon rings. These modifications are small enough that they may not be distinguishable from the Schwarzschild case using current observations from very-long baseline interferometry. The paper also analyzes the effects of dark matter on the accretion disk, considering both isotropically emitting light sources and geometrically and optically thin accretion disks. The results show that the presence of dark matter can significantly affect the observed properties of the black hole shadow and the photon rings, particularly in high-compactness configurations. The study finds that the critical impact parameter for the photon sphere is modified, while the horizon radius remains unchanged. These findings suggest that the optical appearance of black holes in dark matter halos can be significantly different from that of isolated black holes, and that future observations may help distinguish between these geometries.