Archive for: 17-40

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]

c

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Patent: Canon 17-40 f/2.8-4L

Patent: Canon 17-40 f/2.8-4L

Canon EF 17-40 f/2.8-4L Patent
Below is a patent for a new Canon wide angle zoom concept. The variable aperture is interested, if it remained as light and compact as the current 17-40 f/4L, the additional stop of light wide open would be a nice feature.

Patent Publication No. 2010-42792

  • 2012.3.1 Release Date
  • 2010.8.20 filing date

Example 1

  • 39.05mm – f = 17.64 focal length
  • Fno = 2.64 – 4.10
  • 28.99 deg – 50.80 half angle of view.
  • Image height 21.64mm
  • 136.70mm – 134.67 full-length lens
  • BF 39.97 – 64.95mm
  • Lens Construction 12 elements in 9 groups sheet
  • 4 aspherical surface

Canon’s patent

  • Negative lead type zoom lens of negative-positive
  • Small and light lens for focusing
  • Inner focus
  • Focusing the use (1b in the figure) part of the first lens group
  • Video support

Source: [EG]

cr

30 Comments

EF 16-40 f/4L IS [CR1]

EF 16-40 f/4L IS [CR1]

A replacement to the 17-40 f/4L?
Apparently a patent for an EF 16-40 f/4L IS will be filed soon and I’m told to keep an eye for it over the next couple of weeks.

CR’s Take
The 17-40 is one of the best values in “L” lenses and is a cash cow for Canon. It does need improvements on the edges and Nikon stabilized their f/4 full frame wide angle. It’s a believable replacement.

cr


Canon EF 17-40 f/4L $839 @ B&H

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March, Lenses & Stuff

5D Mark III
I keep getting stuff in regards to a March 2011 camera launch. Most people seem to be pointing to a 5D Mark III type of camera. There’s nothing in the way of specs yet.

A good source continues to say a 5D3 replacement will be coming well before a 1Ds3 replacement.

With the production issues with the new lenses, I’m not overly optimistic about a camera body or lenses coming in March. We’ll see how these rumors shake out.

Flash
Received a claim from someone this week that they’re testing a replacement to the 580 EX II.

Lenses
The only lens outside of the regular stuff I’ve received recently has been in regards to a 17-40 f/4L replacement. I’m told to expect it with the march camera launch and it will have IS. I’d CR1 this one.

Where have I been?
Things are slow and I’ve been dealing with being sick, some personal stuff and working on some Canon Rumors improvements.

I am off to Kenya on November 28 and will be returning mid December. I will have internet access for 95% of the trip and will still be checking emails and posting here.

I have a lot of stuff to review while away.

Lens Rentals Canada
If you’re Canadian, I’m offering free shipping until 2011 when you rent a lens or camera body. We’ll still be open when I’m away!

cr

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