As opposed to strong light signals (> 10(8) photons mm(-2) s(-1)), the
construction of images from object sources with low level signals (<1
0(2) photons mm(-2) s(-1)) involves a probabilistic transfer- or point
-spread function. The resulting images carry considerable uncertainty
or spread, restricting resolution and quantification. In this paper we
propose various strategies how to reconstruct object characteristics
from very low light emissions by unfolding the imaging equation. Furth
er. calibration techniques which help to associate light emissions wit
h the decomposition of luminogenic substrates in a spatially selective
way will be discussed.