Canon Patent: 9-18mm F4 IS, 10-20mm F2.8-4 IS And 11-22mm F2.8 IS

Canon Patent
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Here is another Canon patent application.

Canon patent application 2024100498 (Japan, published 7/26/2024) discusses optical formulas or three wide angle lenses:

  • 9-18mm F4 IS
  • 10-20mm F2.8-4 IS
  • 11-22mm F2.8 IS

From the patent literature:

  • A zoom lens that is compact yet has good optical performance even when vibration is reduced is provided.
  • [Background Art]As an imaging optical system used in imaging devices such as digital still cameras, video cameras, broadcast cameras, and security cameras, there is a demand for an optical system that is small and lightweight and has high optical performance even if the amount of image blur correction is large. Patent Document 1 discloses a zoom lens having a subsequent lens group including a first lens group with negative refractive power, a second lens group with positive refractive power, and an anti-vibration lens group, which are arranged in order from the object side to the image side. The anti-vibration lens group performs OIS, which reduces (corrects) image blur caused by shaking of the imaging device due to hand shake or the like (hereinafter referred to as camera shake) by moving (shifting) in a direction perpendicular to the optical axis. In addition, the imaging element that captures the subject image formed by the imaging optical system can perform IIS, which corrects image blur by shifting in a direction perpendicular to the optical axis.
  • In a central projection type imaging optical system, the amount of movement of an image point on an image plane due to camera shake differs between the center and the periphery of the image plane. In particular, the wider the angle of an imaging optical system, the greater the amount of movement of an image point in the periphery compared to the center. For this reason, in an ultra-wide-angle zoom lens with an angle of view exceeding 100°, a lot of image shake remains in the periphery.
  • In the zoom lens of Patent Document 1, the curvature of field during vibration reduction is corrected, but a large amount of residual image blur occurs in the peripheral area due to the difference in the amount of image point movement between the center and the periphery. Also, in the IIS, if the outer diameter of the vibration reduction lens group is large, it becomes difficult to miniaturize the zoom lens.
  • The present invention provides a zoom lens which is small in size and yet has good optical performance even during vibration reduction, and an imaging apparatus using the same.

Example 1

  • Focal length: 10.33-19.39
  • F-number: 4.08-4.12
  • Half angle of view: 61.36-48.13
  • Image height: 18.92-21.64
  • Total length: 128.82-123.27
  • Back Focus: 12.13

Example 2

  • Focal length: 9.20-17.90
  • F-number: 4.08-4.12
  • Half angle of view: 64.04-50.40
  • Image height: 18.90-21.64
  • Overall length: 125.26-119.35
  • Back Focus: 10.50

Example 3

  • Focal length: 11.30-23.90
  • F-number: 4.08-4.12
  • Half angle of view: 59.29-42.15
  • Image height: 19.02-21.64
  • Total length: 129.79-129.33
  • Back focus: 14.54-10.54

Example 4

  • Focal length: 11.30-22.00
  • F-number: 2.89
  • Half angle of view: 59.44-44.52
  • Image height: 19.14-21.64
  • Overall length: 137.35-125.58
  • Back focus: 13.50-10.50

Example 5

  • Focal length: 10.30-19.80
  • F-number: 2.89-4.12
  • Half angle of view: 61.76-47.54
  • Image height: 19.18-21.64
  • Overall length: 132.94-127.01
  • Back Focus: 11.35

Canon RF-S 11-22mm f/4.5-5.6 IS STM To Be Announced Before Summer 2023?

EF-M 11-22mm f/4-5.6 IS STM
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New year, new Canon rumor. A new RF mount lens might be on the horizon. Canon might be set to announce the Canon RF-S 11-22mm f/4.5-5.6 IS STM lens in the first quarter 2023, a rumor suggests.

Say the source of the rumor:

Canon will likely release at least three RF-S lenses in 2023, a couple of them will likely be based on their EF-M counterparts.

One of the lenses we’re told that will launch in the first half of 2023 is an RF-S 11-22mm f/4.5-5.6 IS STM. The EF-M version was a favourite of EOS M shooters since it was launched. It really is a very good lens, especially at its price point.

We think the rumor might be reliable. Time will tell. I own the EF-M 11-22mm and can confirm it is a little gem of a lens. If the RF mount version follows its footsteps, then it might have the following specs:

  • 18-35mm (35mm Equivalent)
  • Aperture Range: f/4.5-32
  • Two Aspherical Elements, One UD Element
  • Dynamic Image Stabilization
  • Spectra Coatings
  • Built-In Stepping Motor

Stay tuned…

Source: Canon Rumors

Canon EF-M 11-22mm f/4-5.6 IS STM review (photozone)

EF-M 11-22mm f/4-5.6 IS STM
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Photozone reviewed the Canon EF-M 11-22mm f/4-5.6 IS STM, one of the five lenses for Canon’s EOS M system. From the conclusion:

Canon has a quite consistent record when it comes to lens quality and this is reconfirmed with the Canon EF-M 11-22mm f/4-5.6 STM IS once again. The resolution characteristic is generally very good except in the extreme corners at 11mm. Image distortions as well as lateral CAs are about average (in the true sense) for a lens in this class. If there’s one substantial weakness, it’s the amount of vignetting. We can’t really tell whether it’s just the lens or the combination with the sensor but the system performance is poor at fully open aperture. However, the transition of the vignetting is fairly smooth – thus less disturbing – and it’s much better at f/8. Read the review…

There is an interesting point discussed in Photozone’s review. The reviewer hypothises that the stron vignetting on the EF-M 11-22mm may be in part also due to the sensor. They suggest the EOS M3 sensor is not optimised for lenses made for mirrorless systems. You can read about this issue here.

Canon EF-M 11-22mm f/4-5.6 IS STM: B&H Photo, Amazon USA, Amazon Canada, Canon Canada, Canon USA

EF-M 11-22mm f/4-5.6 IS STM

Canon EOS M and EF-M 11-22mm IS STM Issue (with firmware 2.0.2)

EF-M 11-22mm f/4-5.6 IS STM Review

Canon EF-M 11-22mm f/4-5.6 IS STM
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A Canon Watch reader (thanks MdB) wrote me an email reporting a strange issue he and another user are having with the Canon EOS M and the EF-M 11-22mm f/4-5.6 IS STM lens. MdB writes:

The problem: If you turn the camera on whilst the lens is already extended the M will not fire off a shot at all. If you turn the camera on and then extend the lens it works perfectly fine. If you turn the camera on with the lens already extended you have to retract the lens and then re-extend the lens and the camera will start shooting again.

The issue appears to show up even with the latest firmware (2.0.2). I tested this on my EOS M and the 11-22mm and could not replicate it.

Does someone here experience the same issue? Would be glad if you can post it in the comments. Thank you.