Photorefractive media are extraordinary candidates for experimental implementation of the lattice soliton concept, because such type of light-induced structures might operate in regimes of weak as well as strong coupling between neighboring wave-guides. Notice that photoinduced structures present possibilities to vary not only the lattice period and refractive index modulation depth but also the value and sign of nonlinearity. Spatial solitons have been demonstrated recently in arrays of optically induced waveguides [I].Here we report experimental results on low-intensity laser beam guiding by periodic array of self-tightening photoinduced lattices. The remarkable self-compression of periodic wave array during propagation in photorefractive SBN crystal (due to the drift-type focusing nonlinearity) is accompanied by decreasing of the lattice width and by growth of refractive index modulation depth. As result, coupling of low-intensity light-waves guided by neighboring lattices diminishes significantly and the number of modes potentially guided by individual lattice steadily decreases. Gradually periodical array of strongly-coupled multimode waveguides transforms into array of weakly-coupled singlemode ones, and this feature enriches possibilities of experimentation with lattice solitons, including the case of discrete spatial solitons. It worth noticing that self-compression is easily controlled by external voltage applied to photorefractive crystal and also that self-tightening of guiding lattices facilitates low-intensity laser beam launching conditions.In the experiment two beams derived from the frequency-doubled diode-pumped YAG:Nd+3 laser (532 am, 50mW) with extraordinary polarization were crossing inside the 6 mm long SBN photorefractive crystal at a small angle (10-2_ 10-3) producing interference fringes with a typical period of 100 gm (Fig.1, right half) that were not practically altered during propagation along the crystal. Additionally, the attenuated relatively wide beam of He-Ne laser ( 633nm, 10 mW) with the same polarization was fed in to the region of green beams intersection (Fig.1, left half, almost uniform input intensity distribution). Naturally that in the absence of the fringes, that form photoinduced lattices, the red beam passes without distortion. The high voltage (up to I kV) application along the c-axis of the crystal (perpendicularly to the fringes) results in the formation of the self-tightening waveguide array by green fringes (Fig. 2, right half). The compression ratio was limited on the level five, approximately, by the development of transverse modulation instability [2]. The red light beam was trapped by this array of self-tightening photoinduced lattices. Fig. 2 (left half) shows corresponding output intensity distribution. It can be seen that profiles of both output waves are not sinusoidal, rather described by elliptical functions, and initially strongly coupled photoinduced waveguides transform in to well separated and practically decoupled ones. Notice that if the read beam i...