The velocity/modulation movie
Each image in camera coordinates was apodized with a cos taper at the limb and then detrended radially and then with a low order polynomial in the x and y directions after masking large magnetic features. The magnetic feature masks were constructed from the modulation observable.
Each image was then registered into Carrington coordinates (720x360 longitude-sin(latitude) grid) and apodized with cos(2*(L-L0)) where L is the Carrington longitude and the L0 is the central meridian of the sub-earth point of the image. The sum of these images was accumulated for all images that contribute to the rotation cycle.
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