A multi-sensor boresight alignment method for a reimaging optical system, the method comprising: receiving a first image frame from a first imaging sensor, the first image frame having an image contrast within a first spectral band and including a first image of a plate positioned at an intermediate image plane of the reimaging optical system, the plate having a pattern of apertures arranged in a surface thereof, the pattern of apertures having a center aperture disposed at substantially a center of the plate; obtaining a first subsection of the first image frame, the first subsection including an image of the center aperture and having a first gate size, wherein the gate size refers to the number of image pixels observable in the image frame; comparing the first gate size of the first subsection to a first gate size threshold, wherein the gate size threshold is a predefined value that is set at a level that ensures that a size of the first subsection is suitable for alignment; adjusting the first gate size and repeating the steps of receiving, obtaining, and comparing for a new first image frame if the first gate size is not within a tolerance range of the first gate size threshold; spot tracking the first subsection to identify a first centroid of the pattern of apertures within the first image frame, wherein the first centroid corresponds to the center aperture, if the first gate size matches or is within a tolerance range of the first gate size threshold; receiving a second image frame from a second imaging sensor, the second image frame having an image contrast within a second spectral band and including a second image of the plate; obtaining a second subsection of the second image frame, the second subsection including an image of the center aperture and having a second gate size; comparing a second gate size of the second subsection to a second gate size threshold; adjusting the second gate size and repeating the steps of receiving, obtaining and comparing for a new second image frame if the second gate size is not within a tolerance range of the second gate size threshold; spot tracking the second subsection to identify a second centroid of the pattern of apertures within the second image frame, wherein the second centroid corresponds to the center aperture, if the second gate size matches or is within a tolerance range of the second gate size threshold; and correcting an optical alignment between the first imaging sensor and the second imaging sensor based at least in part on a position of the first centroid within the first image frame and a position of the second centroid within the second image frame. receiving a first image frame from a first imaging sensor, the first image frame having an image contrast within a first spectral band and including a first image of a plate positioned at an intermediate image plane of the reimaging optical system, the plate having a pattern of apertures arranged in a surface thereof, the pattern of apertures having a center aperture disposed at substantially a center of the plate; obtaining a first subsection of the first image frame, the first subsection including an image of the center aperture and having a first gate size, wherein the gate size refers to the number of image pixels observable in the image frame; comparing the first gate size of the first subsection to a first gate size threshold, wherein the gate size threshold is a predefined value that is set at a level that ensures that a size of the first subsection is suitable for alignment; adjusting the first gate size and repeating the steps of receiving, obtaining, and comparing for a new first image frame if the first gate size is not within a tolerance range of the first gate size threshold; spot tracking the first subsection to identify a first centroid of the pattern of apertures within the first image frame, wherein the first centroid corresponds to the center aperture, if the first gate size matches or is within a tolerance range of the first gate size threshold; receiving a second image frame from a second imaging sensor, the second image frame having an image contrast within a second spectral band and including a second image of the plate; obtaining a second subsection of the second image frame, the second subsection including an image of the center aperture and having a second gate size; comparing a second gate size of the second subsection to a second gate size threshold; adjusting the second gate size and repeating the steps of receiving, obtaining and comparing for a new second image frame if the second gate size is not within a tolerance range of the second gate size threshold; spot tracking the second subsection to identify a second centroid of the pattern of apertures within the second image frame, wherein the second centroid corresponds to the center aperture, if the second gate size matches or is within a tolerance range of the second gate size threshold; and correcting an optical alignment between the first imaging sensor and the second imaging sensor based at least in part on a position of the first centroid within the first image frame and a position of the second centroid within the second image frame.