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Patent: Canon 24-70 f/2.8 Optical Formula and More

Canon Rumors

Who Dey
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Jul 20, 2010
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A patent showcasing a host of optical formulas from Canon has <a href="https://www.canonnews.com/canon-patent-application-variety-of-lenses-discussed">appeared over at Canon News</a>. These patents deal with small focusing groups that allow for light and fast autofocus performance, perhaps more geared to STM than to USM motors being used.</p>
<p><strong>Optical Formulas Covered in the Patent:</strong></p>
<ul>
<li>11-22mm f/4-5.6</li>
<li>24-70mm f/2.8</li>
<li>35mm f/2.8</li>
<li>18-150mm f/3.5-6.3</li>
</ul>
<p>We’re not sure if these are EF, EF-S, or EF-M lenses, or a mixture of all three mounts.</p>
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Focal distance 36.10
F number 2.92
Half field angle 20.73
image height 13.66
Whole length 98.76
BF 35.46

With an image height of 13.66mm, this 35mm lens is an APS-C lens.
The back focus indicates it is for a DSLR.
Therefore this is likely an EF-S mount 35/2.8 lens.

Focal distance 18.56 48.87 145.41
F number 3.60 5.56 6.49
a half field angle -- 36.35 15.62 5.37
Image height 13.66 13.66 13.66
Whole length 103.26 118.62 145.33
BF 10.65 10.65 10.65

Again, 13.66mm means the 18-145 is an APS-C lens.
The BF is for mirrorless.
Therefore likely EF-M mount 18-145/3.5-6.3.

Focal distance 24.76 30.10 67.98
F number 2.92 2.92 2.91
a half field angle -- 41.15 35.71 17.65
Image height 21.64 21.64 21.64
Whole length 198.84 183.00 165.88
BF 38.37 38.37 38.37

The 24-70 is a FF lens (21.64mm image height)
The BF indicates this is for a DSLR.
Therefore likely EF mount 24-70/2.8.

Focal distance 11.33 15.16 21.84
F number 4.10 4.65 5.72
a half field angle-- 50.33 42.03 32.02
Image height 13.66 13.66 13.66
Whole length 88.44 85.64 87.26
BF 9.00 14.02 22.72

The 11-22 is an APS-C lens (13.66mm).
It is more mirrorless (BF is too short for a DSLR).
Therefore likely EF-M mount 11-22/4-5.6.
 
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