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Six ingenious ways how Canon DSLRs used to illuminate their autofocus points

135 points by ExAr

by ExAr

1 subcomments

This article presents the inventive solutions Canon has found to shoot beams of light into the camera's viewfinder in order to light up individual autofocus points. Six different approaches are shown using six Canon DSLR models between 1994 and 2009.

by geocrasher

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My uncle Richard is one of the inventors on Honeywell’s early phase‑detect autofocus. Patent US4333007A, which figures out both the direction and amount the lens needs to move instead of hunting.
Modern systems like Canon’s Dual Pixel AF in bodies such as the EOS R5 are very direct descendants of that idea, just implemented on‑sensor with far more processing power.
Every time I see an article such as this, I beam with pride. (Pun intended).

by Sharlin

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@ExAr I suspect your comment was downvoted to oblivion because people didn't realize you're the OP and thought you were an LLM summarizer bot :(

by generj

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It’s impressive the optical complexity some of these systems use. Custom and complex prisms and mirrors to show the AF points.
Arguably more complicated than the anutofocus optics. The engineering of electromechanical cameras fascinates me.

by BobbyTables2

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I’d really like to know how OP made all those superb visualizations. Must have taken ages!

by brcmthrowaway

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by TheSilva

4 subcomments