When two datasets have been taken of essentially the same experiment, but perhaps with a difference of scaling, this command tries to estimate the scale factor between the two data sets. This process is complicated by signal independent noise such as film fog for film data and electronic noise in many other detectors.
OFFSET/SCALE estimates a signal independent offset and scale factor between two images (one in the memory). For this to be possible there must be a range of intensity values in both images.
(NOTE: This operation is presently under development. Tests show the results to be correct for non-noisy images, but the results in the presence of noise are not very stable. Hopefully the stability can be improved.)