  Images of SN1006 have a number of important properties. For instance, the
bright limbs coincide spatially in various bands, they have different
brightness, and the contrast of brightness varies from radio to gamma-rays. The
reasons of such properties and the role of the magnetic field strength are
discussed. Simple, almost model-independent methods and analytical
approximations for the derivation of the strength of magnetic field from the
comparison of radio, X-rays and TeV images of SNR are presented. The methods
require the TeV image to be well resolved and accurate, at least to the level
of the radio and X-ray maps, in order to put reasonable constraints on magnetic
field. If we apply it to the present HESS data, they limit the strength of
magnetic field in limbs of SN1006 to values lower than few hundreds micro
Gauss. If applied to the Fermi-LAT band, the model predicts same position and
same ratio of the surface brightness for GeV photons as for the radio band. We
conclude that TeV and GeV future high-resolution data may be very informative
about the MF of SN1006.
