Nikon G&D Lens. Compatible with both Nikkor G lens & F lens (include non-AI & AI lens mounts). This adapter reduces focal length to 0.71x, to adjust the image size to near 1:1 so that the focal length of the image is close to actual focal length of the lens, e.g. 50mm x 1.5 x 0.71 = 53.25mm.
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