Archive for: lens

New Canon Lenses Availability – Updated

New Canon Lenses Availability – Updated

Updated – May 25, 2011 @ 9:00PM EST
Canon added dates of December 2011 for the 500 f/4L IS II and 600 f/4L IS II.

thanks Paolo

Update to sales start for EF 300mm f/2.8L IS II USM, EF 400mm f/2.8L IS II USM, EF 8-15mm f/4L Fisheye USM, EF 500mm f/4L IS II USM and EF 600mm f/4L IS II USM lenses
London, UK, 25th May 2011 – Following the announcement of delays to the sales start to the following lenses : EF 300mm f/2.8L IS II USM, EF 400mm f/2.8L IS II USM, EF 8-15mm f/4L Fisheye USM, EF 500mm f/4L IS II USM and EF 600mm f/4L IS II USM, Canon can now provide an update on the planned start dates for these lenses:

  • EF 300mm f/2.8L IS II USM Late August, 2011
  • EF 400mm f/2.8L IS II USM Late August, 2011
  • EF 8-15mm f/4L Fisheye USM Late July, 2011
  • EF 500mm f/4L IS II USM December 2011*
  • EF 600mm f/4L IS II USM December 2011*

Canon would like to apologise to any customers who have been inconvenienced by these delays.

*Any sales start dates will be communicated as soon as they become available.

[source] thanks Eyal

cr

24 Comments

Patent – EF 35 f/1.4L II

EF 35 f/1.4L II

Canon files patent for EF 35 f/1.4L II

  • Patent Publication No. US 7,944,625
  • Published 2011.5.17
  • Filled 2009.8.5

Specifications

  • Focal Distance: 34.59
  • Fno: 1.45
  • Half angle of view: 32.02
  • Image Height: 21.64
  • Lens Length (mm): 126.93
  • Back Focus (mm): 37.98

This is definitely a lens the Canon world wants to see. How do you improve a classic? I’m sure they’ll find a way.

thanks George

cr

Canon EF 35 f/1.4L $1469.00 at B&H

14 Comments

Patent – EF 300 f/4L IS II

EF 300 f/4L IS II

Canon patent for EF 300 f/4L IS II

  • Patent Publication No. 2011-70032
  • Published 2011.4.7
  • Filled 2009.9.25

Specifications

  • Focal Distance: 294
  • Fno: 4.14
  • Half angle of view:4.08
  • Image Height: 21.64
  • Lens Length (mm): 225
  • Back Focus (mm): 83.12
  • Aspherical: 1

Needed? Not really. However the 300 f/4L IS is a great performer and a decent seller for Canon. Adding updated IS to the lens would make most buyers very happy. Not sure it would be upgrade worthy.

cr

Canon EF 300 f/4L IS $1399 at B&H


9 Comments

Patent – EF 24 f/2.8

EF 24 f/2.8

Canon patent for EF 24 f/2.8 USM

  • Patent Publication No. 2011-70032
  • Published 2011.4.7
  • Filled 2009.9.25

Specifications

  • Focal Distance: 24.48
  • Fno: 2.86
  • Half angle of view:38.26
  • Image Height: 21.64
  • Lens Length (mm): 92
  • Back Focus (mm): 38.00
  • Aspherical: 0

This patent is a bit confusing to me. Not sure I see the point of such a lens. Unless Canon is revamping all their affordable primes.

cr


6 Comments

Patent – EF 28 f/1.8 DO & Others

EF 28 f/1.8 DO

Canon files patent for new DO lenses

  • Patent publication 2009-198960
  • Published 03/09/2009
  • Filing date 2008/02/25

Example 1

  • Focal length f = 27.14mm
  • Fno = 1.85
  • Angle of 77.1 °

Example 2

  • Focal length f = 24.50mm
  • Fno = 1.45
  • Angle of 82.9 °

Example 3

  • Focal length f = 25.00mm
  • Fno = 1.45
  • Angle of 81.8 °

Example 4

  • Focal length f = 24.33-36.50-47.00mm
  • Fno = 3.4-4.0-4.7
  • 83.3-61.3-49.4 ° angle

Example 5

  • Focal length f = 26.00-39.00-50.23mm
  • Fno = 3.4-4.0-4.7
  • 79.5-58.0-46.6 ° angle

Information

  • General retrofocus
  • In general SLR wide angle lens
  • Many chromatic aberration
  • Using high-dispersion glass, as excessive compensation around
  • General diffractive optics
  • Can correct chromatic aberrations
  • Where it is difficult to use
  • Manufacturing difficulties
  • Aberration can not fine-lattice

Patented Features

  • Adopted retrofocus
  • Chromatic aberration correction over the entire
  • Diffractive optical elements, aspherical and low dispersion, employing anomalous dispersion lens
  • The lenses focus mechanism
  • Front lens is fixed
  • Second lens to focus
  • Floating mechanism
  • The optical system of patents
  • Lateral chromatic aberration to occur around the first lens
  • Not easily corrected by increasing the number of lenses
  • Diffractive optics correction to put the image side than the diaphragm
  • Only increase the power of the diffractive optical element
  • Chromatic aberration correction using a bonded lens

This is an older patent application, but I think it’s still important to see diffractive optics are not dead within Canon R&D.

cr

3 Comments