Limiting resolution is a simple metric that describes the ability of any image system to distinguish small details of an object. Limiting resolution is normally subjectively calculated from the smallest resolvable group and element in a resolution target such as the USAF 1951 target or analytically from the modulation transfer function MTF of the system. Although limiting resolution has limitations, it provides a quick method with low complexity to establish the performance of an imaging system. Various factors affect limiting resolution such as the optical performance of the system and sensor noise, both temporally and spatially. Evaluating the resolution performance of full motion video FMV results in uncertainty in limiting resolution due to the temporal variation of the system. In high performance FMV system where the modulation associated with the limiting resolution is small, the limiting resolution can vary greatly frame to frame. This paper explores how limiting resolution is measured, factors that affect its uncertainty in FMV system, and provides real world examples from airborne video.
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