1. A duo-frame normalization technique for use in range gate imaging to compensate for phenomenological effects, including the steps of: generating an energy pulse; transmitting over a range interval the energy pulse to a target; simultaneously receiving, a) ambient light present over an open gated range as an integrated ambient image; b) a reflected energy pulse from said target over the open-gated range as an integrated first gate image; c) the reflected energy pulse from said target over a shortened gate range as an integrated second gate image; normalizing the integrated ambient image; subtracting the integrated normalized ambient image from both the integrated first gate image and the integrated second gate image, to yield a first and second frame integration; dividing the second frame integration by the first frame integration whereby a range-coded image is obtained in a time that is relatively short as compared to dynamic scene effects so as to substantially remove all dynamic scene effects from the range-coded image.