Abstract: A method of guiding missiles in the terminal phase of an intercept. An image of the target area is stored as a reference. The reference is expanded by an amount which increases as the missile approaches the target. The expanded reference is then correlated to successively formed images of the target and the results of the correlation are used to guide the missile. The amount of expansion of the reference is selected to compensate for growth of the image as the missile approaches the target. A filter used to filter the successively formed images is adjusted to correspond to the amount of expansion in the reference.