Control effected by hand adjustment of a member that senses indication of a pointer of a built- in light-sensitive device, e.g. by restoring point to a fixed associated reference mark by a follow-up movement of an associated reference mark to the pointer
Control effected by hand adjustment of a member that senses indication of a pointer of a built- in light-sensitive device, e.g. by restoring point to a fixed associated reference mark by a follow-up movement of an associated reference mark to the pointer