New Canon Firmware For Five Telephoto Lenses (1200mm, 800mm, 600mm, 400mm, 100-300mm)

RF 1200mm f/8L
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Canon released firmware updates for five telephoto lenses. Here they are.

Please note: we linked Canon Japan (machine translated) because they are the first to publish the firmware updates.

Have fun…

Canon Patent: 400mm F2.8, 500mm F4 And 600mm F4 Lenses

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New Canon patent for you, ladies and gentlemen. Canon patent application 2024009238 (Japan, published 01/19/2024) discusses optical formulas for three telephoto prime lenses, all for fullframe mirrorless cameras.

  • 400mm F2.8
  • 500mm F4
  • 600mm F4

From the patent literature:

  • [Problem] To obtain an optical system that is lightweight and in which aberrations such as chromatic aberration are well corrected.
  • [ Background Art] As a photographing optical system with a long focal length, a so-called telephoto type photographing system has an optical system with positive refractive power on the object side and an optical system with negative refractive power on the image side. optical system is known. A telephoto type photographing optical system is used, for example, in a single focus super telephoto lens.
  • In a super telephoto lens, generally, as the focal length becomes longer, axial chromatic aberration and lateral chromatic aberration occur more frequently. As a method for properly correcting these chromatic aberrations, it is known to increase the number of lenses arranged on the object side and have each lens share the function of correcting the chromatic aberrations. However, a lens placed on the object side of a super-telephoto lens tends to have a large effective diameter, and if the above-mentioned method is used to correct chromatic aberration, the weight of the photographic optical system increases.
  • In the photographing optical system of Patent Document 1, by arranging a positive lens made of a material having low dispersion and anomalous dispersion continuously from the object side, longitudinal chromatic aberration and lateral chromatic aberration can be corrected. I’m trying.
  • In order to further reduce the weight of the optical system, it is important to find an appropriate material and arrangement not only for the positive lens but also for the negative lens.
  • An object of the present invention is to provide an optical system that is compact and in which aberrations such as chromatic aberration are well corrected, and an imaging device having the same.

Example 1

  • Focal length: 392.00
  • F value: 2.90
  • Half angle of view: 3.16
  • Image height: 21.64
  • Total length: 360.03
  • Back focus: 31.01

Example 2

  • Focal length: 490.00
  • F value: 4.12
  • Half angle of view: 2.53
  • Image height: 21.64
  • Total length: 412.08
  • Back focus: 33.39

Example 3

  • Focal length: 588.00
  • F value: 4.12
  • Half angle of view: 2.11
  • Image height: 21.64
  • Total length: 476.08
  • Back focus: 33.21

All featured Canon patents are listed here.

[via asobinet]

Canon Patent: RF 300mm f/2.8 IS And RF 400mm f/2.8 IS

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And yet another Canon patent application: two telephoto fast primes for the RF mount.

Canon patent application 2023104022 (Japan, published 7/28/2023) discusses optical formulas for two fast telephoto prime lenses for the RF mount: RF 300mm f/2.8 IS and RF 400mm f/2.8 IS.

From the patent literature:

Optical System and Imaging Device Having the Same

Description of the Related Art

An optical system used in an imaging apparatus is required to be compact and lightweight as a whole, and to have high optical performance capable of satisfactorily correcting various aberrations including chromatic aberration. As a compact optical system, a so-called telephoto type optical system is known in which a lens group with positive refractive power is arranged on the object side and a lens group with negative refractive power is arranged on the image side. However, in the telephoto type optical system, the longer the focal length, the larger the entire system, and the use of a lens with a large diameter or a heavy lens tends to increase the weight of the entire optical system.

Example 1

  • Focal length: 294.99
  • F-value: 2.90
  • Half angle of view: 4.19
  • Image height: 21.64
  • Overall length: 280.25
  • Back focus: 37.47

Example 2

  • Focal length: 390.00
  • F-value: 2.90
  • Half angle of view: 3.18
  • Image height: 21.64
  • Overall length: 370.50
  • Back focus: 37.00

More Canon patents are listed here.

[via asobinet]

Canon Patent: 300mm f/2.8, 400mm f/2.8 And 600mm f/4 With Built-in Teleconverter

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A new Canon patent for telephoto lenses with built-in teleconverter. For what mount? RF mount.

Canon patent 2022142979 (Japan, published 10/3/2022) discusses optical formulas for three telephoto lenses with built-in teleconverter. The lenses are 300mm f/2.8, 400mm f/2.8 and 600mm f/2.8. From the patent literature (machine translated):

An object of the present invention is to provide an optical system having a variable power optical system that is inserted into and removed from a main optical system, and to achieve good optical performance while reducing the weight of the entire system.

Description of the Related Art

As a method for changing the focal length of an optical system used in an imaging apparatus, there is a converter method that changes the focal length of the entire system by inserting a variable magnification optical system (extender) in the optical path.

When adopting a system incorporating a variable magnification optical system, in order to achieve good optical performance while reducing the weight of the entire system including the variable magnification optical system, the insertion position of the variable magnification optical system must be appropriately selected. It is important not only to do so, but also to properly configure the main optical system. The invention disclosed in Patent Document 1 has room for improvement from the viewpoint of achieving both weight reduction and optical performance.

Summary of the invention

It is an object of the present invention to achieve good optical performance while reducing the weight of the entire system in an optical system having a variable magnification optical system that is inserted into and removed from a main optical system.

Example 1 ML

  • Focal length: 389.00
  • F-value: 2.91
  • Half angle of view: 3.18
  • Image height: 21.64
  • Total length: 406.00
  • Back focus: 53.83

Example 1 with teleconverter

  • Focal length: 544.00
  • F-value: 4.19
  • Half angle of view: 2.28
  • Image height: 21.64
  • Overall length: 406.01
  • Back focus: 53.83

Example 2 ML

  • Focal length: 582.00
  • F-value: 4.12
  • Half angle of view: 2.13
  • Image height: 21.64
  • Overall length: 486.10
  • Back focus: 81.91

Example 2 with teleconverter

  • Focal length: 814.80
  • F-value: 5.88
  • Half angle of view: 1.52
  • Image height: 21.64
  • Overall length: 486.10
  • Back focus: 81.91

More Canon patents are listed here.

[via asobinet]

Ten Canon EF 400mm f/2.8L IS II Lenses Used To Build The Huntsman Telescope

Canon EF 400mm
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Remember the Dragonfly Telephoto Array? Once more, commercial Canon telephoto lenses are used to build an array to observe and study galaxies and other astronomical objects.

The Canon lenses used to build the new array are the Canon EF 400mm f/2.8 L IS II. The new array, named Huntsman Telescope, is made by Macquarie Unversity with support from Canon, as Australian Photography reports:

Located at the Siding Spring Observatory near Coonabarabran, NSW, the Huntsman will perform deep southern sky surveys to provide researchers with understanding about galaxy formation and evolution; how galaxies form, how they grow, how they engage with structures that surround them, and what happens when galaxies collide.

Canon says the second-generation Canon EF 400mm f/2.8 L lens was chosen for the task as it has ‘superb’ anti-reflection properties, owing to one of the first applications of Canon’s nano-fabricated coatings. Each lens is connected to a red-coloured camera which is then individually connected to one of 10 mini computers.

The coated lens array chosen for the Huntsman contrasts to a conventional mirror telescope, whose imperfectly polished surface can introduce subtle errors that ruin faint, extended structures surrounding galaxies.

Image © Canon

[via PetaPixel]

Canon Patent: 400mm f/4 DO IS Extender 1.4x and 600mm f/4 IS Extender 1.4x

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A new Canon patent application was spotted. 400mm f/4 DO IS Extender 1.4x and 600mm f/4 IS Extender 1.4x are discussed.

Canon patent application 2022-22771 discusses optical formulas for two rather interesting lenses:

  • 400mm f/4 DO IS Extender 1.4x
  • 600mm f/4 IS Extender 1.4x

PROBLEM TO BE SOLVED: To provide an optical system in which a magnification conversion optical group can be inserted and removed and the total length is short.

As a method of changing the focal length of the optical system used for imaging, there is a method of inserting a magnification conversion optical group such as an extender into the optical path . Further, as an optical system in which the total length (distance from the optical surface on the object side to the image surface) does not change due to the insertion / removal of the magnification conversion optical group, Patent Document 1 describes the axial light beam between the aperture stop and the image surface. An optical system capable of inserting and removing a magnification conversion group at a converging position is disclosed.

However, if a space for inserting the magnification conversion optical group is provided between the aperture diaphragm and the image plane as in Patent Document 1, the total length of the original optical system becomes long . Further, if the magnification conversion optical group is inserted in a narrow space, various aberrations of the optical system may increase. The
present invention provides an optical system in which a magnification conversion optical group can be inserted and removed, but the total length is short and good optical performance can be obtained.

Example 1

  • Focal length: 392.58
  • F value: 4.12
  • Half angle of view: 3.15
  • Image height: 21.64
  • Overall length: 280.33
  • Back focus: 36.01

Example 1 (with inserted teleconverter)

  • Focal length: 549.72
  • F value: 5.77
  • Half angle of view: 2.25
  • Image height: 21.64
  • Overall length: 280.33
  • Back focus: 36.00

Example 5

  • Focal length: 585.00
  • F value: 4.12
  • Half angle of view: 2.12
  • Image height: 21.64
  • Overall length: 467.45
  • Back focus: 55.50

Example 5 (with inserted teleconverter)

  • Focal length: 819.18
  • F value: 5.77
  • Half angle of view: 1.51
  • Image height: 21.64
  • Overall length: 467.45
  • Back focus: 55.50

The Canon patent application was spotted by asobinet.com. More Canon patent applications are listed here. Some particularly interesting patent applications we think might get into production are these: