Archive for: 16-35

Patent: A new 16-35 f/2.8 or Faster Concept?

Patent: A new 16-35 f/2.8 or Faster Concept?

Improved Canon ultrawide for full frame?
The world is waiting for Canon to release a top end performing ultra wide lens for full frame cameras. While I think the 17-40 f/4L is a bargain of a workhorse and the 16-35 f/2.8L II is a very solid performer, I think the line is still lacking that standout ultra wide zoom lens. I have heard numerous photographers say they’d pay “anything” for a top notch lens in that segment.

Below are 3 patented optical formulas for new ultrawide angle lenses for Canon.

A 16-35 f/2.8, a 17-35 f/2.8-4 and a 16-35 f/2-2.8. There seems to be a decent amount of f/2 patents appearing on zoom lenses from Canon, it could be time for such a lens to make it to market.

Patent Publication No. 2012-63568

  • 2012.3.29 Release Date
  • 2010.9.16 filing date

Example 2

  • Zoom ratio 2.06
  • 24.00 – - 33.95mm f = 16.48 focal length
  • Fno 2.90 – 2.90 – 2.91
  • 42.03 – - 32.51deg 52.70 angle of view.
  • Image height 21.64mm
  • 170.87 – - 172.62mm 178.10 full-length lens
  • BF 40.00 – 48.45 – 61.71mm
  • Lens Construction 12 group 17 sheets
  • Three three aspherical surface
  • 2 UD lens sheet

Example 4

  • Zoom ratio 1.94
  • 24.01 – - 33.98mm f = 17.51 ​​focal length
  • Fno 2.91 – 3.21 – 3.86
  • Image height 21.64mm
  • 174.18 – - 175.92mm 178.81 full-length lens
  • BF 41.60 – 48.49 – 60.70mm
  • Lens Construction 12 group 17 sheets
  • Three three aspherical surface
  • 2 UD lens sheet

Example 6

  1. Zoom ratio 2.06
  2. 24.02 – - 33.99mm f = 16.49 focal length
  3. Fno 2.15 – 2.46 – 2.94
  4. 42.02 – - 32.48deg 52.69 angle of view.
  5. Image height 21.64mm
  6. 171.08 – - 172.88mm 176.23 full-length lens
  7. BF 39.26 – 46.99 58.75mm
  8. 18 sheets 13 group lens configuration
  9. Three three aspherical surface
  10. 2 UD lens sheet

Canon’s patent

  • 4-group zoom lens of a positive negative positive and negative
  • Inner Focus
  • Optimized so as to reduce the field curvature of the wide-angle side

Source: [EG]

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Friday Deals @ B&H

Friday Deals @ B&H

From B&H
The 5D Mark II w/24-105 f/4L IS kit at $2799 until December 11, 2011. (BUY)

The EF 70-200 f/2.8L IS II is at $2074, which is about $425 cheaper than it was in the summer. (BUY)

The Canon 580 EX II is now $399, that’s a savings of $50. (BUY)

The EF 16-35 f/2.8L II is at $1394 until midnight EST tonight. You’re saving about $220. (BUY)

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Canon EF 16-35 f/2.8L II $220 Off

Canon EF 16-35 f/2.8L II $220 Off

From B&H
More aggressive pricing from B&H on Canon gear. They seem to be going beyond the Canon rebate pricing.

You can get the Canon EF 16-35 f/2.8L II for $220 off at B&H until December 8, 2011.

Buy for $1394.00 @ B&H 

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Canon 16-35 f/2.8 DO Patent

Canon 16-35 f/2.8 DO Patent

More lens patents
This is an interesting DO patent from Canon. There seems to be a lot of them showing up, but no new DO products in a long while.

I’ve been told the lack of an A+ filterable wide angle from Canon for a full frame camera will be addressed sooner than later. Yes, there’s Zeiss, but most want AF.

Patent Publication No. 2011-145518

  • Release Date 2011.7.28
  • Filing date 2010.1.15

Example 1

  • Focal length f = 16.48 – 24.00 – 33.95 mm
  • Fno = 2.91
  • Half angle of 52.70 – 42.04 – 32.51 °
  • 4 aspherical surfaces
  • Zoom Ratio 2.06
  • Four-group zoom lens plus a negative sign
  • Second lens focusing is performed by Inner Focus
  • Solve various problems using the diffractive optical element
  • The astigmatism of the telephoto kept in order, to increase the refractive index of the positive lens
  • A high refractive index, chromatic aberration occurs
  • Aberration and astigmatism in the center of the telephoto image has a correlation, it is difficult to simultaneously correct
  • Made achromatic diffractive optical element, a positive lens astigmatism correcting high refractive index

Source [EG]

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