PetaPixel

Coming to a Camera Near You: Autofocus As Fast as the Human Eye

Contrast detection is one of the two main techniques used in camera autofocus systems. Although focusing speeds continue to improve, the method uses an inefficient “guess and check” method of figuring out a subject’s distance — it doesn’t initially know whether to move focus backward or forward. UT Austin vision researcher Johannes Burge wondered why the human eye is able to instantly focus without the tedious “focus hunting” done by AF systems. He and his advisor then developed a computer algorithm that’s able determine the exact amount of focus error by simply examining features in a scene.

His research paper, published earlier this month, offers proof that there is enough information in a static image to calculate whether the focus is too far or too close. Burge has already patented the technology, which he says could allow for cameras to focus in as little as 10 milliseconds.

(via ScienceNOW via Fast Company)


Image credit: 2011 12×12 Vancouver Photo Marathon by 12×12 Vancouver Photo Marathon


 
 
  • http://twitter.com/whitehotphoenix White Hot Phoenix

    This is exciting!

  • http://www.flickr.com/photos/throughpaintedeyes/ Through Painted Eyes

    The clearest glass we’ve ever seen, and now autofocus to die for…exciting times!!

  • Dave

    ….for those of you who are really in such a hurry to capture an image that normal, alreadyrealfast auto-focus isn’t enough……Let me guess, this new technology will go primarily to the point and shoot cameras favored by snapshooters.

  • http://www.flickr.com/photos/throughpaintedeyes/ Through Painted Eyes

    Why do you think it would primarily go to p&s cameras?

  • Dave

    Because consumer grade cameras are the ones that sell in the millions. I have never met a pro that complains about auto-focus speed. The cameras I use have incredible auto-focus speed and things keep getting better. Look at the first two replies to this post. How slow must their cameras be responding for them to make such enthusiastic replies…..or have they only been involved with photography for a couple weeks? After all face recognition first went to the p&s market. Yes, I know more serious cameras are now incorporating it but not from necessity. Serious photographers are more likely to spend time on composition and focus and their cameras are most likely equipped with perfectly competent af systems. Plus, hopefully, they are able to recognize faces all on their own.  The p&s shooter on the other hand, should feel better about a feature that he/she read about in the sales info that they can regurgitate when talking to others about the shiny new camera they have and how rad it is. New photographers seem to latch on to any new trend such as this. They also tend to buy p&s cameras. Hope this helps.

  • Ian Crane

    Sports shooters will give their right arm for faster auto-focus, its all about catching that instantaneous moment. 

  • Dave

    Which they have been doing a fine job of for years. How? High end slrs do not have an issue with fast auto-focus. Have you ever once heard a pro complain about af speed? Neither have I, because it is not an issue. This is either destined for p&s cameras or as vaporware. Your comment shows your lack of real field experience with pro cameras.

    ” its all about catching that instantaneous moment”

    That is what all cameras do btw. Even you taking snapshots of cuddles the cat.

  • wickerprints

    The one thing you’re missing is that a rapid, accurate, and precise AF performance based on the statistical method described in the paper would obviate the need for a reflex mirror if an electronic viewfinder is used.  This would have numerous advantages:  (1) no VF blackout; (2) shorter shutter lag time; (3) faster frame rate; (4) EVF shows true DOF and background blur for fast-aperture lenses; (5) AF functions at all f-numbers provided sufficient EV and subject contrast; (6) AF point can be selected from any arbitrary point in the image; (7) quieter operation; (8) fewer moving parts means more robust bodies; (9) optical system need not require long flange focal distances to accommodate a mirror, thus permitting more flexible optical design of retrofocus and normal lenses.

    And these are just the obvious advantages for “professional” photography, should this proposal come to fruition.  The high-accuracy, high-speed phase-detection AF system in present-day DSLRs is the key reason why such cameras still continue to have mirrors.  The optical VF enabling a TTL view was the historical reason for SLR technology, but with the advent of high-performance, high-resolution EVFs, this is no longer the limiting factor.  In fact, I would go so far as to say that this idea has vastly more potential to revolutionize high-end digital photography than the consumer point-and-shoot market, and the processing power that it would require would probably necessitate it being introduced on high-end bodies with large sensors before it found its way into cheap compact cameras, for which most owners don’t even need such AF performance, both in terms of speed and accuracy.

  • kendon

    i’m with dave on this one. try a canon 1d or even a 7d and then evaluate again if there might be a need for a faster autofocus. at 8+ fps you get more than enough keepers, and the pictures that aren’t good wouldn’t be better with a fast af. the speed of these cameras is close, if not up to what a human can handle. what wickerprints says might be true, but then there’s that evf thing…

  • Igogosh

    In light of what Sony is pushing for in their current SLT series of cameras, they might as well drop this “semi translucent” mirror completely and go on with their EVF using this technology.

  • Mrbeard

    Would be a great feature if it improved low light focusing, using manual at poorly lit gigs can be frustrating even with a fast lens

  • Chris

    I respectfully disagree.  You’ve thought this through much better than most of the posters, but I have so far been quite unimpressed with electronic viewfinders.  Most of your high end AF lenses are full time manual override for a reason: people who put food on their table with their images don’t trust AF.  That’s not because of technical limitations is phase detection AF, either.  If AF was perfect and instant I still wouldn’t trust that it focused on the bird I’m photographing and not the (higher contrast) grass behind it.  So I still want to sanity check focus with the viewfinder, which brings up the question of which more accurately produces the image in the viewfinder, flat glass or an EVF.  Given the 1MP display on the back of the D90 (which I would guess is better than you’re going to get in an EVF with a viewing cup to cut down on glare) I still pick direct projection on glass.  And if I’m using a mirror and glass anyway, I’m better off with phase detection.

  • B64

    ” I have never met a pro that complains about auto-focus speed.”

    LOL! Not sure how many pro’s you meet on a day-to-day basis, but… pro cameras (such as the Canon 1D Mk IV or 1D X, or Nikon D3s) are the quickest focusing camera’s around, by some margin. And lens-based AF motors are way more powerful and quick on pro lenses than those on kit lenses.
    You think that’s a coincidence?

    OK, a pro landscape shooter is typically less concerned about focusing speed, but professional photojournalists can’t have a camera that focuses quickly enough

  • Dave

    ” Not sure how many pro’s you meet on a day-to-day basis, but… pro
    cameras (such as the Canon 1D Mk IV or 1D X, or Nikon D3s) are the
    quickest focusing camera’s around, by some margin. And lens-based AF
    motors are way more powerful and quick on pro lenses than those on kit
    lenses.”

    Thank you for reiterating what I have been saying. I deal with pros all the time, I am in the business myself. Even if your camera has 100X faster autofocus that is currently available, there is nothing in the world saying it is focused on what you want it to be focused on.

  • Dave

    ” Not sure how many pro’s you meet on a day-to-day basis, but… pro
    cameras (such as the Canon 1D Mk IV or 1D X, or Nikon D3s) are the
    quickest focusing camera’s around, by some margin. And lens-based AF
    motors are way more powerful and quick on pro lenses than those on kit
    lenses.”

    Thank you for reiterating what I have been saying. I deal with pros all the time, I am in the business myself. Even if your camera has 100X faster autofocus that is currently available, there is nothing in the world saying it is focused on what you want it to be focused on.

  • Anonymous

    Before electronics in cameras people were doing perfectly fine without autofocus. It’s not necessarily mandatory, but in today’s context, faster AF helps. 

  • Anonymous

    You’re right, but an important practical reason you missed in your discussion is that SLRs use generally use phase detection to detect focus, which is fast and doesn’t need to use the image sensor at all, and doesn’t require complex image analysis to tell where the focus should go.

  • Dave

    Actually, you missed my point entirely. I am saying this new system sounds like fluff. No camera can tell you where to focus.

  • Anonymous

    If you think it’s fluff, why didn’t you say it that way in the first place?

    Also, you misunderstood me.  It’s not about the camera telling you where to focus, I was meaning the camera telling the lens where to go. I don’t see anything in this method that precludes the ability to set a focus point.