This work presents an experimental study on the diffuse and localized deformation mechanisms of a high porosity (20%) Vosges sandstone (Eastern France) subjected to different stress paths, orthogonal to the initially isotropic state. The experimental campaign was performed using a high pressure true triaxial apparatus (TTA) in which the three principal stresses are independently controlled. A series of 10 quasi-static, monotonous loading tests was performed at two constant mean stress, in the brittle-ductile transition regime, and at five prescribed Lode angles, from axisymmetric compression (ASC) to axisymmetric extension (ASE), as a measure of the deformation mode. The failure surface in each deviatoric plane and changes in macroscopic measurements, such as dilatancy and deformation band angles, tracked by full field digital image correlation technology, indicate a clear effect of the Lode angle on a transition between the brittle and ductile regime, independent from the total mean stress level.