As a matter of fact metric cameras always used central shutters. These shutters enabled an exposure which is done at the same time on all parts of the image. This means that the mid exposure time, and thus the projection center of images taken with a moving camera, is invariant in image space. Unfortunately these central shutters are restricted in exposure time range. Under aerial imaging conditions, they should only be used in combination with forward motion compensation, which minimizes smear effects. Focal plane shutters are able to produce short exposure times. So smear effect is minimized as good as possible. It gets especially important when Bayer arrays are used and no FMC is available. Also mid exposure time is no longer space invariant. Focal plane shutters produce geometrical effects in the images and influence measuring accuracy. We studied these effects and implemented a compensation method. In our paper we show the study results for the influences and our method to compensate the shutter effects. The compensation was applied to test flight data. These results will be shown too.
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