Canon Patent: 12-24mm f/2.8 And 14-20mm f/2 For RF-Mount

Canon Patent

Here is a new Canon patent application, as usual for RF-mount lenses.

Canon patent application 2024042622 (japan, published 3/28/2024) discusses optical formulas for two lenses for full frame mirrorless cameras (i.e. fort he RF-mount):

  • 12-24mm f/2.8
  • 14-20mm f/2

From the patent literature:

  • An object of the present invention is to provide an ultra-wide-angle zoom lens that is compact and provides high optical performance over the entire object distance range.
  • [ Background Art] As an imaging optical system, an imaging lens with a half angle of view of more than 50 degrees at the wide-angle end is called an ultra-wide-angle lens, and among them, a bright lens with an F value of 2.8 or less has a wide Suitable for taking advantage of the angle of view and short shutter speed for shooting starry skies and dark places. Such an ultra-wide-angle lens is required to have high resolution performance that suppresses spherical aberration and sagittal flare over a short distance from an infinite subject. Particularly in zoom lenses, there has been a problem in that it is difficult to reduce the size of the lens while suppressing variations in aberrations from the wide-angle end to the telephoto end.
  • However, the zoom lens disclosed in Patent Document 1 has a large F value and cannot sufficiently reduce aberration fluctuations during zooming due to an increase in aperture. The zoom lens of Patent Document 2 reduces aberration fluctuations during zooming by having multiple groups compared to the zoom lens of Patent Document 1, but there is a need for a wider angle and a smaller size.
  • An object of the present invention is to provide an ultra-wide-angle zoom lens that is compact and provides high optical performance over the entire object distance.

Example 1

  • Focal length: 12.29-23.80
  • F value: 2.93
  • Half angle of view: 60.39-42.27
  • Image height: 21.64
  • Total length: 138.05-134.83
  • Back focus: 13.86-19.48

Example 2

  • Focal length: 14.30-21.50
  • F value: 2.06
  • Half angle of view: 56.54-45.18
  • Image height: 21.64
  • Total length: 148.04-139.46
  • Back focus: 13.87-20.30

More Canon patents are listed here.

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Today Only: Sigma 12-24mm f/4 DG HSM Art Lens (EF mount) – $899 (reg. $1599)

Sigma 12-24mm

Only for today (5/24/2023) B&H Photo has a whooping $700 discount on the awesome Sigma 12-24mm f/4 DG HSM Art lens for Canon EF mount.

At a glance:

  • EF-Mount Lens/Full-Frame Format
  • Aperture Range: f/4 to f/22
  • Five FLD Elements, One SLD Element
  • Three Aspherical Elements
  • Super Multi-Layer Coating
  • Hyper Sonic Motor AF System
  • Rounded 9-Blade Diaphragm
  • Built-In Lens Hood

Get the Sigma 12-24mm f/4 DG HSM Art lens for Canon EF mount on sale at $899. Compare at $1,599.

If you want to learn more about this fantastic Sigma lens, have a look at Dustin Abbott‘s video-review below.

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Laowa 12-24mm f/5.6 C-Dreamer Lens Review (DPREview TV)

Laowa 12-24mm F/5.6

DPReview TV reviewed the Laowa 12-24mm f/5.6 C-Dreamer lens. Sample pictures taken with the lens are here.

The 12-24mm f/5.6 zoom is an ultra-wide zoom lens designed for mirrorless cameras. With an angle of view from 84° to 121°, the lens can be very useful for multiple scenarios. It also has a fixed f/5.6 maximum aperture throughout the whole zoom range which gives the photographer much greater control over the photo. The lens is relatively lightweight in its class. It is compressed to be around 3.3″/ 84mm long and weighs about 1.09lbs/ 497g. The lens is also compatible with 77mm filters (With the lens hood) and has a 15cm close-focusing distance. Easily creating interesting shots with good background separation. Like many of the Laowa lenses, this wide-angle lens also renders stunning 10-point sunstars.

Laowa 12-24mm f/5.6 Zoom Lens For RF Mount (and others) Announced

Laowa 12-24mm

A new Laowa lens has been announced: the Laowa 12-24mm f/5.6 Zoom for full frame mirrorless cameras. The 12-24mm f/5.6 Zoom is currently available to purchase via Venus Optics official website and authorized resellers. It is priced at $649 for Canon RF, Sony E and Nikon Z while $699 for Leica M.

Venus Optics’ press release:

Anhui China, 7 July 2022 – Venus Optics, the camera lens manufacturer that has been endeavoringto invent high-quality lenses at an affordable price, is thrilled to release an ultra-compact Zoom Lens for Full Frame cameras -Laowa 12-24mm f/5.6 Zoom. This tiny lens offers an AOV from an ultra-wide 121.9° to an easier-to-control 84° with a fixed aperture. The 5.9”/15cm closest focusing distance allows users to explore more creative shots or even macro-like photos. Laowa’s classical 5-bladed aperture design for stunning 10-point Sunstar also packed in this lens. A 77mm filter can be used directly with the adaptor ring (come along with the lens). With the competitive price of USD649 (USD699 for m mount) and the tiny size, this lens would be perfect for travel and landscape photography. Canon RF, Sony E, Nikon Z and Leica M are available for this lens.

Wide-angle zoomin a compact body With an 84° to 121.9° zoom range, the lens provides greater flexibility to photographers in framing. Users could adjust the focal length easily with a twist. The lens is relatively compact and light in its class. It is measured to be ⌀69.4x84mm(⌀2.73×3.30”) with a lightweight 497g(1.09lbs).A great option for photographers who wants to pack lightweight.

A constant f/5.6 aperture

The lens has a constant f/5.6 aperture which the aperture does not change when adjusting the focal length. Photographers would have greater control over the photos.

15cm closest focusing distance

The lens has one of the shortest close-focusing distances in the 12-24mm market. It can focus only 5.9”/15cm away from the sensor, giving photographers more room for creative shots such as macro-like shots.

Minimize distortion

Despite it’s not one of the members of the Laowa Zero-D class, the lens still demonstrates an extreme well control performance in minimizing distortion.Still extremely useful for architecture or interior shots when you want the flexibility of a zoom lens at the same time.

Stunning 10-point Sunstar

Like many other Laowawide-angle lenses, this 12-24mm is designed with a 5-bladed aperture which could render appealing 10-point Sunstar when slightly stepping down the aperture.

77mm filter thread

The 12-24mm Zoom lens is able touse a 77mm filter with the adaptor ring that comes with the lens. The ring is also able to act as a lens hood and protect your image from flaring.

“Frog-Eye” coating

The lens had coated with the water & dust repelling “Frog-Eye” Coating (FEC). It gives your lens an extra layer of protection compared to traditional coatings.

Sigma 12-24mm f/4 ART Deal – $1149 (reg. $1599, today only)

Sigma 12-24mm F/4 Art Deal DG HSM

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Get the Sigma 12-24mm f/4 DG HSM Art lens on sale at $1,149. Compare at $1,599. Free shipping.

Sigma 12-24mm f/4 ART Deal key features:

  • EF-Mount Lens/Full-Frame Format
  • Aperture Range: f/4 to f/22
  • Five FLD Elements, One SLD Element
  • Three Aspherical Elements

All hand-picked deals are listed here (odds are good some are still live).

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Canon Patent For 20mm f/1.4 and 12-24mm f/4.3-5.6 Lenses For EF Mount

Canon Patent

Hi Lows Note spotted a Canon patent application (2019-128526, Japan) describing optical formulas for a 20mm f/1.4 and a 12-24mm f/4.3-5.6 lens, both for the Canon EF mount.

20mm f/1.4 lens:

  • Focal length: 20.50 mm
  • FNo.: 1.44
  • ω: 46.54
  • Image height: 21.64 mm
  • Lens length: 134.70 mm
  • Back focus: 36.81 mm

12-24mm f/4.3-5.6 lens:

  • Focal length: 12.40 – 18.00 – 23.64 mm
  • FNo.: 4.35 – 4.96 – 5.60
  • ω: 60.18 – 50.25 – 42.47
  • Image height: 21.64 mm
  • Lens length: 142.18 – 132.82 – 131.14 mm
  • Back focus: 36.14 – 44.23 – 52.29 mm

More Canon patent applications are listed here. Some particularly interesting patent applications we think might get into production are these: