  An analysis is made on the morphology of the sequences, formed by stars
distributed along the line of sight in (V,V--I) colour-magnitude diagrams from
Baade's Window (l=1.0,b=-3.9). The extinction is due to an absorbing layer with
an effective thickness of about 100 pc. A linearly, with distance, increasing
extinction up to a maximum value inside the absorbing layer is in first order a
good approximation for the actual extinction present along the line of sight.
We show that the morphology of the disc sequence gives a good indication of the
nearby extinction along the line of sight. The morphology of the bulge/bar red
horizontal branch is likely due to a combination of differential reddening and
a significant metallicity spread among the horizontal branch stars. This is
irrespective of the type of extinction law adopted. There is in Baade's Window
globally no big difference between a Poissonian or a patchy type of extinction,
except for substructures in the morphology of the sequences for the latter.
