This paper investigates the optical appearance of a spherically symmetric black hole surrounded by a dark matter halo, both when orbited by isotropically emitting light sources and when surrounded by a geometrically and optically thin accretion disk. The black hole geometry is coupled to an anisotropic fluid with a Hernquist-type density distribution, forming a dark matter halo. The study finds minor modifications to the primary and secondary tracks of isotropic orbiting sources and the width, location, and relative luminosity of the corresponding photon rings compared to a Schwarzschild black hole at equal black hole mass and emission models. These findings pose challenges in distinguishing between the two geometries using current observations, such as those from very-long baseline interferometry. The paper also analyzes the impact of high compactness configurations on the geodesic structure, including the formation of additional photon spheres and stable circular orbits, which can affect the structure of accretion disks and the observed images. The results highlight the importance of considering the compactness of the dark matter halo in understanding the observational properties of these systems.This paper investigates the optical appearance of a spherically symmetric black hole surrounded by a dark matter halo, both when orbited by isotropically emitting light sources and when surrounded by a geometrically and optically thin accretion disk. The black hole geometry is coupled to an anisotropic fluid with a Hernquist-type density distribution, forming a dark matter halo. The study finds minor modifications to the primary and secondary tracks of isotropic orbiting sources and the width, location, and relative luminosity of the corresponding photon rings compared to a Schwarzschild black hole at equal black hole mass and emission models. These findings pose challenges in distinguishing between the two geometries using current observations, such as those from very-long baseline interferometry. The paper also analyzes the impact of high compactness configurations on the geodesic structure, including the formation of additional photon spheres and stable circular orbits, which can affect the structure of accretion disks and the observed images. The results highlight the importance of considering the compactness of the dark matter halo in understanding the observational properties of these systems.