Egami, the Japanese Photography blog has uncovered Canon patents for a EF 24-70mm f/2.8L IS and a EF 24-80mm f/2.8L IS lenses. You can read the (translated) article here. The recently introduced EF 24-70mm f/2.8L II lens lacks Image Stabilization and is not a very good value for the money even though the lens is a top performer.
Patent Publication No. 2013-182246
- Publication date 2013.9.12
- Filing date 2012.3.5
Example 1
- Zoom ratio 2.75
- Focal length f = 24.70-36.42-67.88mm
- Fno. 2.91
- Half angle ω = 41.22-30.71-17.68 °
- Image height 21.64mm
- 164.87-172.85-196.79mm overall length of the lens
- BF 39.07-44.44-54.56mm
- 20 pieces of 13-group lens configuration
- Four four-sided aspherical
Example 2
- Zoom ratio 2.76
- Focal length f = 24.70-34.88-68.18mm
- Fno. 2.91
- Half angle ω = 41.22-31.81-17.61 °
- Image height 21.64mm
- 165.79-174.26-199.67mm overall length of the lens
- BF 38.47-42.81-58.00mm
- 20 pieces of 15-group lens configuration
- Three 3 aspherical surface
Example 3
- Zoom ratio 3.22
- Focal length f = 24.70-39.67-79.43mm
- Fno. 2.91
- 41.22-28.61-15.24 ° angle of view
- Image height 21.64mm
- 161.98-171.74-200.99mm overall length of the lens
- BF 38.35-46.17-57.64mm
- 20 pieces of 13-group lens configuration
- Four four-sided aspherical
Canon patent
- 5-group zoom of positive and negative positive positive and negative
- Antivibration (fourth lens group)
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