  For the magnetic shape memory effect, knowledge about the interaction between
martensitic and magnetic domain structure is essential. In the case of Ni-Mn-Ga
bulk material and foils, a staircase-like magnetic domain structure with
90{\deg}- and 180{\deg}-domain walls is known for modulated martensite. In the
present paper we show that the magnetic domain pattern of thin epitaxial films
is fundamentally different. Here we analyze epitaxial Ni-Mn-Ga films by atomic
and magnetic force microscopy to investigate the correlation between the
twinned martensitic variants and the magnetic stripe domains. The observed
band-like domains with partially perpendicular outof-plane magnetization run
perpendicular to the microstructure domains defined by twinning variants. These
features can be explained by the finite film thickness, resulting in an
equilibrium twinning period much smaller than the domain period. This does not
allow the formation of a staircase domain patter. Instead the energies of the
magnetic and martensitic microstructures are minimized independently by
aligning both patterns perpendicularly to each other. By analyzing a thickness
series we can show that the observed magnetic domain pattern can be
quantitatively described by an adapted band domain model of Kittel.
