Imaging systems in which an undedicated optical component—i.e., a component that would be present in the system even in the absence of image stabilization—is configured to undergo corrective motion and/or other correction of image data, and thus to function as a stabilization component. The stabilization component may be a mirror and/or a lens, and a positioner may be provided to tilt, rotate, and/or otherwise precisely adjust the position and orientation of the stabilization component to improve image resolution, compensate for platform motions, and/or improve image tracking. Because an undedicated optical component functions as the stabilization component, the stabilization occurs upstream, rather than downstream, from separation (if any) of the incoming image data into two or more beams. As a result, only one stabilization component is required regardless of whether the system is configured to split the image data into multiple data channels, and imaging systems as described herein therefore may be particularly well-suited for integration into a shared-aperture imaging system.