A printing press for processing sheet printing materials includes at least
one printing unit, a computer and a measuring device for monitoring
printing quality during a printing process. The measuring device has a
sensing device for measuring by color or spectrally to register the
printing material. At least one sheet-guiding element leads the sheet
printing material past the sensing device. A measuring device for
monitoring printing quality during a printing process in a printing press
for processing sheet printing materials, is also provided.