в материале тюли во вкладке options переключите opacity mode на normal. или перекиньте карту фоллофф в слот рефракт
Opacity mode – this parameter controls how the opacity map works. The possible values are:
Normal – in this mode, the opacity map is evaluated as normal, the surface lighting is computed and the ray is continued for the transparent effect. The opacity texture is filtered as normal.
Stochastic – in this mode, the surface is randomly shaded as either fully opaque or fully transparent so that on average it appears to be with the correct transparency. This mode reduces lighting calculations but might introduce some noise in areas where the opacity map has gray-scale values. The opacity texture is still filtered as normal.
Clip – in this mode, the surface is shaded as either fully opaque or fully transparent depending on the value of the opacity map (i.e. without any randomness). This mode also disables the filtering of the opacity texture. This is the fastest mode, but it might increase flickering when rendering animations.For more information, see the Opacity mode parameter example below.
