Conventional sensors have a limited dynamic range. This means
that high-contrast scenes may have solid black shadows, blown
highlights, or both, depending on the exposure compromises you
and the camera make.  This happens because the individual
pixels, or photosites, on the sensors can only cope with a
certain brightness range. At one end of the range, they don't
capture enough photons to register any kind of signal; while at
they other they capture so many that they're saturated.  What
you need is a sensor with different-sized photosites: larger
ones for everyday photography; and some smaller, lower-
sensitivity sites for hanging on to detail in highlights.
Fujifilm's SR sensor is the only one to tackle this issue.  Its
combination of large S-type pixels and smaller R-type pixels
offers a dynamic range up to 400 per cent wider than that of
conventional sensors. The FinePix S5 Pro uses this SR sensor, as
did its predecessor, the S3 Pro, and the design has also been
tried out in a couple of Fujifilm compacts.