Archive for: supertelephoto

Patent: 600 f/4 DO IS & 400 f/2.8 DO IS

Patent: 600 f/4 DO IS & 400 f/2.8 DO IS

Patent Time!
More diffractive optic patents from Canon. This time, another 600 f/4 IS DO lens and a 400 f/2.8 DO IS.

With the cost of the new super telephotos from Canon, I can’t imagine what new DO lenses would cost.

Continue reading for the patent breakdown….

Patent Publication No. 2012-88427

  • 2012.5.10 Release Date
  • 2010.10.18 filing date

Example 1

  • Focal length f = 585.00mm
  • Fno 4.12
  • Image height 21.64mm
  • Length 468.50mm lens
  • BF 90.78mm
  • 15 sheets of 9 group lens configuration
  • One aspherical surface a
  • 2 UD glass sheet
  • One fluorite
  • A plane diffraction

Example 2

  • Focal length f = 391.86mm
  • Fno 2.88
  • Image height 21.64mm
  • Length 367.51mm lens
  • BF 50.01mm
  • Lens Construction 14 elements in 9 groups sheet
  • 2 2 aspherical surface
  • 1 UD glass sheet
  • One fluorite
  • A plane diffraction
  • Group 3 consists of positive and negative positive
  • Inner Focus (group 2)
  • Strengthen the refractive power of the front lens group, and to shorten the overall length, the sensitivity is increased, it is difficult to manufacture and assembly
  • The number of lens group at the end of the super-telephoto lens is determined by the balance of the total length and chromatic aberration
  • And shorten the length and reconcile, the correction of chromatic aberration, the number will increase
  • It is important to the length of each degree
  • Weight of the first lens group, 70% to 9 on the whole
  • Canon patents is reduced to three the first group
  • Aspherical and one eye in group 1 group, field curvature correction, the distortion
  • Diffractive optical element and the second two groups in the first group, the chromatic aberration correction

Source: [EG]

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Lets Play Chess

Lets Play Chess

I hear Canon won.
A couple of gents at LensRentals.com got bored during their move to new digs and decided to play some chess!

Canon won the game with a Fischer like performance.

I know what you’re thinking. Can you rent this chess set? The answer is yes!

For $7654.75 you can rent this chess for a 4 days, this will include the damage insurance for when you knock your king over after a terrible loss.

What about buying it? Sure can! $151,202.17 you can buy the pieces necessary to do this at home. As LensRentals.com mentions, buy now before the new Canon supertelephotos hit the market. The price will skyrocket. To entice you even more, they’ll throw in a free t-shirt!

Read More: Blog Post | Rental Post

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