A new Canon patent application. Canon patent application 2023107573 (Japan, published 8/3/2023) discusses optical formulas for three telephoto lenses:
800mm f/5.6 IS
1000mm f/8 IS
1200mm f/8 IS
From the patent literature:
An object of the present invention is to provide an optical system in which various aberrations are satisfactorily corrected while being compact and lightweight, and an imaging apparatus having the optical system.
Description of the Related Art
A telescopic optical system used in an imaging apparatus is required to have a long focal length and a small F-number (large aperture). Patent Documents 1 and 2 disclose a first lens group with positive refractive power, a second lens group with positive or negative refractive power, and a third lens group with positive or negative refractive power, which are arranged in order from the object side to the image side. An optical system is disclosed, consisting of lens groups, with a second lens group moving during focusing.
Here, it is also desired that the telescopic optical system be compact and lightweight, and that various aberrations such as chromatic aberration and spherical aberration are well corrected. However, when trying to increase the aperture of a telescopic optical system, the effective diameter of the lens arranged on the object side becomes particularly large, making it difficult to reduce the size and weight of the entire system. Therefore, in order to realize the above-mentioned demands, it is important to appropriately set the optical arrangement of each lens group that constitutes the optical system, and the refractive power and arrangement of each lens that constitutes each lens group.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an optical system in which various aberrations are satisfactorily corrected while being compact and lightweight, and an imaging apparatus having the optical system.
The Canon RF 800mm f/11 IS STM gets a lot of positive reviews, and they are listed here. Also interesting: an interview with the engineers who developed the lens.
Here is a fresh Canon RF 800mm f/11 IS STM review.
At a glance:
RF-Mount Lens/Full-Frame Format
Fixed f/11 Aperture
Retractable, Locking Lens Barrel
Gapless Dual-Layer Diffractive Optics
STM Stepping AF Motor
Optical Image Stabilizer
Customizable Control Ring
Compatible with RF Extenders
The Canon RF 800mm f/11 IS STM Review comes from Admiring Light. The review is rather positive, comes with sample pictures. From their conclusion:
The Canon RF 800mm f/11 IS STM continues the trend of unique and relatively high quality consumer-grade lenses from Canon. […] When the lens was first announced, like many I dismissed it immediately as too slow and limited. If you are in that camp, and you want a lightweight and compact lens with a lot of reach, I would strongly recommend trying out this lens.
I was quite pleased to see that image quality is very good for such an optic. While not reaching the lofty heights of Canon’s big white supertelephotos, the RF 800mm f/11 produces images with good sharpness, nice bokeh and an overall pleasing rendering that punches above its price point and weight. The biggest compromise for that size, cost and reach is the fixed f/11 aperture, which means that this lens is going to require higher ISOs for fast shutter speeds, especially in lower light situations. The slow aperture also limits the autofocus area, which can make it a little more difficult to track subjects.
Nikon releases the NIKKOR Z 800mm f/6.3 VR S, a super-telephoto prime lens for the Nikon Z mount system
Realizing dynamic shooting of distant subjects such as wild birds and other wildlife handheld or with a monopod
TOKYO – Nikon Corporation (Nikon) is pleased to announce the release of the NIKKOR Z 800mm f/6.3 VR S, a super-telephoto prime lens that is compatible with full-frame/FX-format mirrorless cameras for which the Nikon Z mount system has been adopted. The development of this lens was announced on December 14, 2021.
The NIKKOR Z 800mm f/6.3 VR S, featuring the longest focal length of 800 mm among NIKKOR Z lenses, employs a PF (Phase Fresnel) lens for the first time in the NIKKOR Z lineup, realizing approx. 48% reduction in weight and approx. 16% in length compared to the AF-S NIKKOR 800mm f/5.6E FL ED VR. It not only facilitates shooting handheld or with a monopod, but also allows users to capture images of wild birds and other wildlife in mountain areas, reducing the burden during long hours of picture-taking and transportation.
The NIKKOR Z 800mm f/6.3 VR S belongs to the S-Line* lens series that pursues the ultimate in optical performance. In addition to the PF lens element, ED glass and SR lens elements are employed to compensate chromatic aberration for minimized color bleeding, allowing accurate depiction of even the finest feathers of distant wild birds. The adoption of Nano Crystal Coat, as well as the optimized shape and location of the PF lens element also contribute to reducing ghost, achieving clearer images. Furthermore, with the lens’ center of gravity positioned closer to the body side, the NIKKOR Z 800mm f/6.3 VR S is optimal for shooting moving subjects such as airplanes, because users are less aware of the weight of the lens even if it is swung around during panning. High operability and superior rendering performance support reliable use of this lens by many users ranging from advanced amateurs to professional photographers.
Nikon will continue to pursue a new dimension in optical performance while meeting users’ needs, contributing to the development of imaging culture, with the hope of expanding possibilities for imaging expression.
Primary features
Focal length can be extended to 1,120 mm with the Z TELECONVERTER TC-1.4x, and 1,600 mm with the Z TELECONVERTER TC-2.0x while maintaining outstanding resolution*1.
Focal length can be extended up to 1,200mm-equivalant without a teleconverter by setting the camera’s image area to [DX (24×16)] format.
The optical VR function that provides a superior compensation effect equivalent to shooting at a shutter speed 5.0 stops*2 faster is incorporated. When paired with the Z 9, the effect of 5.5 stops*2 is achieved with Synchro VR activation.
The employment of an STM ensures high-speed and accurate AF with quiet operational sounds.
Superior dust- and drip-resistant performance*3, outstanding reliability with robustness and weather resistance, and anti-fouling performance with the adoption of fluorine coat.
Anti-slip rubber coating is applied to a larger area of the lens body, ensuring more comfortable holding.
Four L-Fn2 buttons and one L-Fn button to which a wide variety of functions can be assigned are adopted to suit users’ preferences.
The supplied lens hood featuring an improved lock mechanism enables attachment and removal with one hand even on a large-diameter lens.
Employs the Memory Recall function*4 that instantly recalls focus positions that have been stored in advance, via pressing an assigned button.
A design considering video recording including a focus-breathing compensation function which effectively reduces shifting of the angle of view when focusing, and stable exposure.
Go Long: Canon Introduces the RF800mm F5.6 L IS USM and RF1200mm F8 L IS USM Super-Telephoto Lenses
The Newest RF Lenses are Ideal for Outdoor Sports, Motor Sports, Wildlife Photography, Photo News Journalism, and More
MELVILLE, NY, February 23, 2022 – Canon U.S.A., Inc., a leader in digital imaging solutions, is excited to announce that the Canon RF lens family is growing by two, with the addition of the Canon RF800mm F5.6 L IS USM, and the longest focal length RF lens yet, the RF1200mm F8 L IS USM. Both super-telephoto fixed focal length lenses are quite light for their considerable abilities, and share many of the same features such as Super Spectra Coating (SSC) and Air Sphere Coating (ASC) to help minimize ghosting and flaring, compatibility with both the RF1.4x and RF2x extenders and a customizable electronic focusing ring with manual focus capability during Servo AF.
Additional features shared by both lenses include:
Two focus presets, with the ability to instantly switch between memorized focus distances
Circular nine-bladed aperture providing photographers with exceptionally beautiful and soft blurred backgrounds and bokeh
Renowned Canon L-Series durability and construction with dust and water resistance, plus fluorine coating on the front element for easy cleaning
Canon RF800mm F5.6L IS USM The RF800mm F5.6 L IS USM weighs in at just 6.9 lbs and features a minimum focusing distance of 8.53ft/2.6 meters — maximum close-up magnification is a superb 0.34x, allowing wildlife image creators to fill the frame with small subjects, such as birds, at its minimum focusing distance. Optical image stabilization is up to 4.5 stops* of shake correction and includes three IS operation modes. When using the RF1.4x or RF2x extenders, users can experience enhanced effective focal lengths of 1,120mm and 1,600mm respectively.
Canon RF1200mm F8 L IS USM The RF1200mm F8 L IS USM is the most powerful super-telephoto lens in the Canon RF lens line. It weighs in at 7.4 lbs — an outstandingly light figure for a super-tele lens of this type — and features a minimum focusing distance of 14.1ft/4.3m. Optical image stabilization is up to 4.0 stops* of shake correction and, similar to the RF800mm F5.6 L IS USM lens, includes three IS operation modes. When using the RF1.4x or RF2x extenders, users can experience enhanced focal lengths of 1,680mm and 2,400mm, respectively.
Pricing and Availability The Canon RF800mm F5.6 L IS USM and Canon RF1200mm F8 L IS USM are both scheduled to be available in late May 2022 for an estimated retail price of $16,999.00 and $19,999.00, respectively**. For more information please visit usa.canon.com.
This website or its third-party tools use cookies, which are necessary to its functioning and required to achieve the purposes illustrated in the cookie policy. If you want to know more or withdraw your consent to all or some of the cookies, please refer to the cookie policy. By closing this banner you agree to the use of cookies.