Eye-Controlled Focus: A New Vision For Photography

Eye-controlled autofocus (AF) is a technology that allows a camera to focus on whatever the user is looking at. Canon first introduced this technology in 1992 with the EOS A2E (also known as the EOS 5), the world's first SLR camera with eye-controlled focus. While the system had its limitations and was eventually shelved, Canon has since reintroduced eye-controlled AF in its EOS R3 camera, released in 2021. The new system is more advanced and reliable, working in tandem with the camera's subject tracking capabilities. It also features improved eye detection, thanks to Canon's work in medical imaging, and can be calibrated for up to six different users or eyewear setups.

Eye Control AF was first introduced by Canon in 1992 with the EOS A2E

Canon's Eye Control AF, a technology that allows users to focus their camera simply by looking at their desired point of focus, was first introduced in 1992 with the EOS A2E (also known as the EOS 5 in European markets). This camera was a prosumer SLR with a range of advanced features, including a 5-point autofocus system, a large built-in flash, and various exposure modes. The eye-controlled focus technology was revolutionary for its time, but it had mixed results depending on the user, with some photographers experiencing eye strain and others finding that slight eye movements caused the focus to shift or blur. Despite these challenges, the EOS A2E gained popularity with professionals due to its robust feature set, excellent handling, and reliability.

The EOS A2E was not the only camera to feature Eye Control AF. This technology was included in a few other 35mm film SLRs and camcorders before being shelved with the emergence of digital SLRs and features like multi-controllers. However, Canon continued to innovate and improve its autofocus systems, eventually releasing the EOS R5 in 2020, which offered full-screen autofocus. The latest evolution of Eye Control AF was introduced in the EOS R3, a mirrorless camera with refined Eye Control AF capabilities.

The feature was later seen in the EOS 50 (1995), EOS 3 (1998) and EOS 30 (2000)

The Canon EOS 50, also known as the Elan II in America and the EOS 55 in Japan, was released in September 1995. It was an autofocus, autoexposure 35mm SLR camera aimed at advanced amateur photographers. The EOS 50 featured an enhanced version of the 3-zone eye-controlled autofocus system, first introduced on the EOS 5. This system allowed for faster and more precise focusing, bringing the camera's performance a step closer to matching the human eye.

The Canon EOS 3, released in 1998, was a high-end SLR camera for professionals and advanced amateurs. It featured an improved Eye Controlled Focus system, making it almost twice as fast and more precise than its predecessor. The EOS 3 also offered 45-point Area AF, 7 fps high-speed predictive AF continuous shooting mode, and an array of custom functions for a more versatile shooting experience.

In October 2000, Canon introduced the EOS 30 (also known as the EOS Elan 7e in America and the EOS 7 in Japan). This camera retained the eye-controlled focusing feature, while its identical twin, the EOS 33/ELAN 7, did not. The EOS 30 built upon the advancements of its predecessors, offering a range of innovative features and improved performance, catering to the needs of both professional and advanced amateur photographers.

These three cameras, the EOS 50, EOS 3, and EOS 30, played a significant role in the evolution of eye-controlled focusing technology, with each iteration refining and enhancing the system to provide photographers with a more intuitive and responsive autofocus solution.

Canon's Medical Systems division helped develop the technology

Canon's Medical Systems division has played a pivotal role in the development of eye-controlled focusing technology for cameras. This technology, known as Eye Control AF, enables photographers to focus their camera precisely on what they are looking at through the viewfinder.

Canon Medical Systems Corporation, formerly Toshiba Medical, was acquired by Canon Inc. in 2016. The company is headquartered in Ōtawara, Tochigi, Japan, and has a long history of innovation in medical imaging, including being an early pioneer of X-ray tubes in Japan as far back as 1914.

Canon Medical Systems' expertise in medical imaging and its partnership with Canon Inc. have likely contributed to the development of eye-controlled focusing technology for Canon cameras. The medical imaging expertise of the division would have provided valuable insights into the technical aspects of eye-tracking and image capture.

Additionally, Canon Medical Systems' work in artificial intelligence (AI) and advanced imaging technologies may have also played a role in refining the Eye Control AF feature. Canon Medical Systems has developed AI-assisted total workflow experiences and AI deep learning reconstruction technologies, which could have informed the development of Eye Control AF's subject-tracking capabilities.

The division's focus on clinical specialties, such as interventional cardiology, interventional oncology, and radiology, may have also contributed to a deeper understanding of the human visual system and how it interacts with imaging technologies. This knowledge could have been leveraged to enhance the accuracy and reliability of eye-controlled focusing in Canon cameras.

Canon's Medical Systems division, with its rich history, innovative capabilities, and expertise in medical imaging, has undoubtedly played a pivotal role in bringing eye-controlled focusing technology to life, revolutionizing the photography experience for Canon users worldwide.

The system uses LEDs and infrared light to detect what you're looking at

Eye-controlled focusing is a feature that allows a camera user to select a focusing point simply by looking at it. This feature was first introduced by Canon in 1992 with its EOS A2E camera.

The system uses LEDs and infrared light to detect what the user is looking at. Infrared light, or infrared waves, are part of the electromagnetic spectrum. While humans cannot see infrared light with the naked eye, it can be detected as heat. Remote controls, for example, use light waves just beyond the visible spectrum of light—infrared light waves—to change channels on a TV.

Infrared light is divided into near-, mid-, and far-infrared. The region from 8 to 15 microns (µm) is referred to by Earth scientists as thermal infrared since these wavelengths are best for studying the long-wave thermal energy radiating from the planet. The wavelength of infrared light is usually between 500nm to 3000nm in length.

Infrared light is also used in heat lamps, which emit both visible and infrared energy. These lamps can be used to heat bathrooms, keep food warm, and keep small animals and reptiles warm.

In 1800, William Herschel discovered infrared light when he conducted an experiment measuring the difference in temperature between the colors in the visible spectrum. He placed thermometers within each color of the visible spectrum and found that the temperature increased from blue to red. When he noticed an even warmer temperature measurement just beyond the red end of the spectrum, he had discovered infrared light.

Today, night-vision goggles and infrared cameras allow us to "see" the infrared waves emitting from warm objects such as humans and animals. Similarly, eye-controlled focusing technology in cameras uses LEDs and infrared light to detect what the user is looking at and immediately focus on it.

The feature is designed to work in tandem with the Canon EOS R3's subject tracking

Eye Control AF is a feature that allows users to select a focusing point by simply looking at it through the viewfinder. This is achieved through the use of LEDs and a specialised sensor inside the viewfinder that can detect the position and direction of the user's eye. The feature is designed to work in tandem with the Canon EOS R3's subject tracking, allowing photographers to quickly switch between subjects without having to manually adjust the focus point.

For example, in a fast-paced situation like a cheetah going in for a kill, a photographer might want to switch their focus from the cheetah to a lion suddenly attacking. With Eye Control AF, they can do this simply by looking at the new subject in the viewfinder, rather than having to use the Multi-controller to nudge the AF point across. This can help ensure that crucial moments are not missed.

Once the new subject is selected, the camera's subject tracking takes over, and there is no need for the photographer to continue staring at the subject. The camera will continue to track and focus on the subject as it moves. This allows the photographer to focus on composition and be more aware of new potential subjects entering the frame.

The Eye Control AF system can be activated by pressing the Set button. When the shutter button is pressed halfway, a grey box will appear around any eyes or faces detected in the scene. The user can then select the desired target by looking at it, and pressing the shutter button fully. The box will turn blue, and the camera will begin tracking the subject.

The system can be customised to the user's eyes and any eyewear they may use. It is also possible to change the shape and colour of the Eye Control AF pointer to make it more visible or to see smaller details of the subject.

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