A method, comprising: receiving (205, 305, 505) a sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) of an object, wherein at least two consecutive images of the sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) are spatially shifted relative to each other; transforming (210, 310, 510), by a processor, each image (f i) in the sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) into a Fourier domain using a Fourier transform to generate a corresponding plurality of Fourier transformed images (F i); calculating (215, 315A-315C, 515A, 515B), by the processor, an amplitude filtered pattern in the Fourier domain based on amplitude components of the plurality of Fourier transformed images (F i); determining (220, 320A-320C, 520A-520C 5), by the processor, spatial shifts for pairs of consecutive images (f i f i+1) in the sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) using the amplitude filtered pattern; aligning (225, 325, 525), by the processor, images in the sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) based on the determined spatial shifts; and characterized in that the method further comprises summing (230, 330, 530), by the processor, the aligned images to form an image-shift-corrected summed image, and in that the amplitude filtered pattern calculation (215, 315-A-315C, 515A, 515B) comprises: summing (315A, 515A) the amplitude components of the Fourier transformed images (F i) to generate an amplitude pattern (F A); applying (315B, 515B) an amplitude threshold to the amplitude pattern (F A) to generate the amplitude filtered pattern, wherein the amplitude filtered pattern includes pixels in the amplitude pattern (F A) having an amplitude at or above the amplitude threshold. receiving (205, 305, 505) a sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) of an object, wherein at least two consecutive images of the sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) are spatially shifted relative to each other; transforming (210, 310, 510), by a processor, each image (f i) in the sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) into a Fourier domain using a Fourier transform to generate a corresponding plurality of Fourier transformed images (F i); calculating (215, 315A-315C, 515A, 515B), by the processor, an amplitude filtered pattern in the Fourier domain based on amplitude components of the plurality of Fourier transformed images (F i); determining (220, 320A-320C, 520A-520C 5), by the processor, spatial shifts for pairs of consecutive images (f i f i+1) in the sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) using the amplitude filtered pattern; aligning (225, 325, 525), by the processor, images in the sequence of images ( f 1 ( x,y), ( f 2 ( x,y),..., ( f n ( x,y)) based on the determined spatial shifts; and characterized in that the method further comprises summing (230, 330, 530), by the processor, the aligned images to form an image-shift-corrected summed image, and in that the amplitude filtered pattern calculation (215, 315-A-315C, 515A, 515B) comprises: summing (315A, 515A) the amplitude components of the Fourier transformed images (F i) to generate an amplitude pattern (F A); applying (315B, 515B) an amplitude threshold to the amplitude pattern (F A) to generate the amplitude filtered pattern, wherein the amplitude filtered pattern includes pixels in the amplitude pattern (F A) having an amplitude at or above the amplitude threshold. summing (315A, 515A) the amplitude components of the Fourier transformed images (F i) to generate an amplitude pattern (F A); applying (315B, 515B) an amplitude threshold to the amplitude pattern (F A) to generate the amplitude filtered pattern, wherein the amplitude filtered pattern includes pixels in the amplitude pattern (F A) having an amplitude at or above the amplitude threshold.