Magnetic field distribution in the quiet and active photosphere

The presentation is intended to describe results obtained with the UNNOFIT inversion of spectropolarimetric data. Quiet regions of the Sun are studied on the one hand, where the structure of the magnetic field remains unresolved and is approached via a magnetic filling factor. It is got that the field is structured in thin flux tubes connected by loops at any altitude in the solar atmosphere. The fluxtube diameter size is evaluated. On the other hand, active regions are studied, in particular sunspots where the magnetic field horizontal gradient is found one order of magnitude weaker than the vertical gradient, as in other observations reported in the literature. This is a difficulty to ensure \hbox{${\rm div}\vec{B}=0$}. Before entering the results, the particular features of the UNNOFIT inversion are recalled, which concern essentially the magnetic filling factor modeling