  Effects of macro-and microlensing on the spatial and temporal characteristics
of images of remote sources, observed through the inner regions of lensing
galaxies are discussed. A particular attention was given to the case, when
microlenses, - stars, star-like or planetary bodies, - are situated near the
critical curves of macrolenses, - galaxies, stellar clusters, etc. The
investigation is of interest for the gravitational lens (GL) systems, where the
lensed images are observed close to the critical curve of a macrolens. Annular,
arched or confluent images should be regarded as an indication to such a
proximity. Numerical simulation allowed to determine the structure of critical
curves and caustics, formed by macro and microlenses, and to evaluate possible
distortions, caused by microlenses for various locations with respect to the
critical curve of a regular lens. The difference of our results from those
obtained earlier with the standard (linearized) approach to describe the
regular gravitational lens was shown to be the larger the closer to the
critical curve the microlenses are situated. In addition to spatial
redistributions in the visible images, complicated deformation of their light
curves occurs in gravitational lensing of variable in time and extended
sources. The magnitude of the temporal variations depend not only on the GL
parameters (e.g., mass distribution), but on the parameters of the source as
well, such as linear dimension of the emitting region, its location with
respect to the critical curve, and the impulse duration. The analysis shows,
that in this case GL acts as a filter, which passes slow temporal variations
without degradations, and smoothes the rapid ones.
