Collecting roll data associated with a sensing and mating rolls that form a nip uses first and second pluralities of sensors. Each sensor of the first plurality has a corresponding sensor in the second plurality which is associated with a same respective axial location on the sensing roll but is spaced-apart circumferentially. The sensors are located at axially spaced-apart locations of the sensing roll and generate either a first or second respective signal when entering the nip. Upon receiving a generated signal, a determination is made about which sensor generated the received signal and the membership of that sensor in one of the pluralities. Based upon a rotational position of the mating roll, a determination is made of which tracking segment associated with the mating roll enters the region of the nip concurrently with the signal to store the signal using the determined one tracking segment and the determined membership.