Effect of film development on uniformity and modulation transfer function of the gated/fast x-ray imagers data

We have been investigating the different phenomena that affect the modulati on transfer function response of the gated x-ray imagers and fast x-ray ima gers that we use to record subnanosecond x-ray images at different laser fa cilities. As part of that investigation, we noticed that there is definite nonuniformity to the recorded images, even when the incident radiation was uniform. After a significant effort to track down that effect we found that the automatic developing processors, which process the film along the leng th of the roll, cause the effect. Manual development, which depends primari ly on transverse agitation in the developer, and automatic processors that do not use a feed mechanism but emulate this agitation, do not introduce su ch artifacts. We recommend that for absolutely critical missions, such as t arget symmetry measurements, certain automatic machines should not be used.