How did eye-controlled autofocus work on the Canon EOS 5?
Asked 1/20/2013
3 views
2 answers
0
The Canon EOS 5 was advertised as having eye-controlled autofocus. I understand it used infrared eye tracking to choose an AF point, but I’d like a clearer explanation of the mechanism. How did the camera detect where you were looking in the viewfinder, and did it require any calibration?
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
13y ago
2 Answers
9
What is Eye-Control Focus(ECF)?
Through the tracking of eyeball movements, EOS cameras equipped with eye-controlled focusing (ECF) are able to choose the appropriate autofocus point based on where the user is looking in the viewfinder frame. (wikipedia)
How it works
More information can be found on the Photonotes.org Canon EOS Beginners’ FAQ Copyright © 2002-2013 NK Guy
A series of tiny infrared LEDs (light emitting diodes) shine harmless infrared energy onto your eyeball as you peer through the viewfinder. Light sensors record the infrared reflecting off your eye and calculate the focus point. A computer in the camera then examines this data and decides which of the focus points is closest to that point and selects it. If the camera is in AI Servo mode then it will also adjust focus automatically based on that selected point.
Originally by user4892. Source · Licensed CC BY-SA 4.0
user4892
13y ago
0
Generated from our catalog & community — verify before relying on it.
Canon’s Eye-Control Focus worked by tracking your eye while you looked through the viewfinder, then mapping that gaze position to one of the camera’s autofocus points.
In simple terms, small infrared LEDs inside the viewfinder shone harmless IR light onto your eye. Sensors measured the reflections from your eye/cornea, and the camera’s processor estimated where in the viewfinder you were looking. It then selected the AF point closest to that position. In AI Servo mode, it could continue adjusting focus as the subject moved.
Yes, the system required calibration so the camera could learn how your eye’s reflections corresponded to gaze direction. Community sources indicate the EOS 5 used preset/factory calibration profiles rather than fully custom user-created calibration.
So the key idea is: IR illumination + reflected-light sensing + calibration + software mapping to the nearest AF point. It wasn’t literally focusing on your eye; it was using your eye direction as an input method for AF-point selection.
Recommended products
UniqueBot
AI13y ago
Your Answer
Related Questions
Why did eye-controlled autofocus disappear from modern cameras?
What are the benefits of having many autofocus points?
Do more phase-detect AF points improve focus accuracy on mirrorless cameras?
What happens inside a DSLR when you manually select a different autofocus point?
Does having only one cross-type AF point affect the Canon 6D’s low-light focusing?