  A hairy Schwarzschild black hole describes the deformation of Schwarzschild
black hole due to including additional sources. It is found that depending on
the hairy parameters, the photons' configurations around this black hole can be
classified into two cases, corresponding to the hairy Schwarzschild black hole
with single photon sphere and double photon spheres, respectively. We focus on
the shadows and images of the hairy Schwarzschild black hole under two types of
static thin illuminations conditions: disk accretion and spherical accretion,
respectively. Under both illuminations, the two hairy parameters ($\alpha$ and
$l_o$) have competitive effects on the shadow and optical appearance image of
the hairy Schwarzschild black hole with single photon sphere. This means that
even though the parameters have significant influences on the rings and
shadows, its images with certain groups of $\alpha$ and $l_o$ could be
indistinguishable to that of Schwarzschild black hole, namely, the degeneracies
of images raise between the hairy Schwarzschild black hole and Schwarzschild
black hole. Moreover, the optical appearance image of the hairy Schwarzschild
black hole with double photon spheres will exhibit new additional rings and
accretion features, which {are not} present in the images of (hairy)
Schwarzschild black hole with single photon sphere. Our theoretical studies on
the rings and shadows provide a potential tool to differentiate the hairy
Schwarzschild black hole with double photon spheres from Schwarzschild black
hole, but they are not always helpful for the cases with single photon sphere
due to the degeneracies.
