  Studies of the long-term spectral variations have been used to constrain the
emission processes of black hole candidates. However, a common scenario which
is able to explain the emission from soft to hard X-rays has been proposed only
recently. Here, we use XMM and INTEGRAL data on 1E 1740.7-2942 in order to
demonstrate that Comptonization plays an important role in producing high
energy photons, as predicted by the current modeling scenario.
