CRC (Close Range Correction System)
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One of the many pioneering efforts from Nikon, system that provides superior picture quality at close focusing distances and increases the focusing range of a lens. Through “Floating Element” designs -wherein each lens group moves independently to achieve focusing- CRC enables selected Nikkor lenses to provide comparable performance at both very near and very far focusing distances. For fisheye, wide angle and micro lenses, CRC allows for most interesting perspectives. A most impressive example of a lens with this feature is the AF-S 17-35mm f/2.8D ED IF Zoom Nikkor. CRC is also used in some selected medium telephoto Nikkor lenses.
