From the Canon Imaging Plaza YouTube Channel:
See what’s deep inside the EF200-400mm F4L IS USM Extender 1.4x. Made up of hundreds of precise mechanical and optical parts, the EF200-400mm F4L IS USM Extender 1.4x is a super telephoto lens that opened up new possibilities for professionals on the front line of sports, nature and news photography.
Canon unveils the precise inner construction of this L lens that has not been visualized before. This video was filmed using stop motion animation method.
B&H carries the Canon EF 200-400mm f/4L IS USM 1.4x Ext. lens.
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