Sigma Patent 200mm F2 DG OS HSM Sports Lens and a TELE CONVERTER 1.4x, the 200mm ART lens is of Sports edition and features a F2 aperture range, a excellent companion to carry around for shooting sports of wildlife photography. However a patent tales roughly 2-3 years of time to convert itself into a real product.
Sigma also filed patent for 1.4X tele converter
Take a look at the translated text below
- Patent Publication No. 2016-45314
- Published 2016.4.4
- Filing date 2014.8.21
- The master lens
- Focal length 194.93
- F-number 2.05
- Full angle of view 2ω 12.70
- The image height Y 21.63
- Overall length of the lens 231.33
- BF 60.2233
- Complex lens
- Focal length 274.52
- F-number 2.89
- Full angle of view 2ω 9.06
- The image height Y 21.63
- Overall length of the lens 252.18
- BF 39.5088
- [0058] Incidentally, the main lens used in the embodiments of the present invention is directed to an imaging optical system disclosed in Example 1 of JP 2008-145584. However, the main lens is not limited to this.
- [0059] In order to properly carry out the evaluation of the chromatic aberration in the examples were fitted a known glass types in Example 1 of Japanese Unexamined Patent Publication No. 2008-145584.
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This is a patent for 1.4x tele converter appealed by Sigma， the 200mm F2 lens in which is
Canon’s EF 200mm F2L IS USM appealed at 2008.