Celestron Nature DX 12x50 ED BinocularsCelestron Nature DX 12x50 ED Binoculars employ ED objective lenses to reduce color fringing around high contrast subjects (chromatic aberration). The view is also improved by fully multi coated lenses throughout the binocular and phase corrected BaK 4 prisms. The polycarbonate chassis is rubber armored and O ring sealed and nitrogen purged to make it water and fogproof. Usually we expect a degradation in field of view and close focus in a 12x50, but