Plural image planes are illuminated through a single image-collecting objective system. The field of view or magnification (or both), is allocated dynamically among the plural planes. Preferably the planes include two detector planes—one corresponding to a wide field of view (FOV) and the other to a steerable narrow one. Allocation is performed by a beam splitter in combination with a steering mirror, or steering-mirror array, that steers both fields together. The splitter isolates radiation corresponding to the narrow FOV from radiation corresponding to the wide FOV. In method forms of the invention, an electrooptical observation system produces simultaneous plural images for a region of interest. The system displays simultaneous images having respective plural resolutions. In operation a first, relatively wider FOV continuously covers a region of interest; while the second is narrower and has finer resolution than the first.