New new Canon 24-70mm F2.8 IS Lens Patent surfaced over the web today, So the upcoming 24-70mm Lens will have IS but the latest announced 24-70mm F2.8L II lens is still unavailable to users and expected to arrive at stock till september 2012, canon is doing some final changes in the lens before it goes in the production line,
Translated by Google
Self-interpretation and summary, Patent Document
- Patent Publication No. 2012-123156
- 2012.6.28 Release Date
- 2010.12.8 filing date
- Example 1
- Zoom ratio 2.46
- 68.99mm – f = 28.00 focal length
- Fno. 2.88
- 17.41 deg – 37.69 half angle of view.
- Image height 21.64mm
- 222.38mm – 192.25 full-length lens
- BF 39.98 – 53.68
- Effective diameter 74.47mm ball before
- Effective diameter aperture 31.23mm
- 19 sheets 12 group lens configuration
- Three three aspherical surface
- 2 UD glass sheet
- Example 2
- Zoom ratio 2.86
- 68.70 – f = 24.00 focal length
- Fno. 2.88
- 17.48 deg – 42.03 half angle of view.
- Image height 21.64mm
- 224.86mm – 191.93 full-length lens
- BF 39.85 – 55.68mm
- Effective diameter 77.29mm ball before
- Effective diameter aperture 32.58mm
- Lens Construction 12 group 21 sheets
- Three three aspherical surface
- 2 UD glass sheet
- Five-group zoom positive and negative positive positive and negative
- (For Focusing group 2) Inner Focus
- (Part 1 of the fourth lens group, anti-vibration unit is L4a) image stabilization
- Positive refractive power of the first lens group
- The aberration can be corrected and weaken, the lens is larger
- Difficult to correct aberration and strengthen
- The amount of movement of the second lens group and one, the first
- Must be strengthened to reduce power and refraction, aberration correction is difficult
- Diameter of the first lens group becomes larger and more
via egami
