Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 68,767   Posts: 1,484,173   Online: 869
      
Results 1 to 6 of 6
  1. #1
    Mainecoonmaniac's Avatar
    Join Date
    Dec 2009
    Shooter
    Multi Format
    Posts
    2,728
    Images
    6

    Shutter speed iPhone app

    I have the Shutter Speed app for iPhone and I find it hard to use. Maybe someone can make an app that uses the camera that actually measures the shutter with the camera by measuring duration of the light instead of using the sound of the shutter?
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
    Aaron Chang

  2. #2

    Join Date
    Jun 2009
    Location
    Boston, MA
    Shooter
    Medium Format
    Posts
    545
    It's probably not very practical for higher speeds. In order for something like that to work, you'd need to be using the CMOS sensor in the iPhone in "video" mode, where it's constanly exposing and "waiting" for the light to hit the sensor. And since the frame rate for iPhone cam is 30fps, reallly the fastest shutter speed you can measure using that is 1/30s. I'm guessing that the Shutter Speed app you have can go faster than that?

  3. #3
    M Carter's Avatar
    Join Date
    Jan 2013
    Location
    Dallas, TX
    Shooter
    Medium Format
    Posts
    97
    I was thinking this over the other day - something like this would likely work with the slowest iphone "shutter" speed, and measure how much of the light is scanned. The iPhone has such a low scan rate for the sensor though (that's why you get "jello" when you move the phone - things like phone poles become slanted). I doubt the sensor is scanned fast enough to do faster shutter speeds.

    Ever slide a document around on a xerox machine or scanner bed while the light is moving across the glass? That's essentially what happens with digital sensors (they're moving much faster, but same effect).

    But the calculation would likely be based on "size" - how many rows of pixels get illuminated, divided by the sensor scan time. Which would likely change based on distance between the shutter and the phone's camera. My best guess anyway.

  4. #4
    Mainecoonmaniac's Avatar
    Join Date
    Dec 2009
    Shooter
    Multi Format
    Posts
    2,728
    Images
    6
    So many smart APUGers! So how useful is using sound sound from a clicking shutter to measure speed like the iPhone app?
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
    Aaron Chang

  5. #5

    Join Date
    Jun 2009
    Location
    Boston, MA
    Shooter
    Medium Format
    Posts
    545
    I've done shutter speed test using sound recorded with a microphone connected to a computer. It's pretty good up to 1/60s or so. Better option is this product: http://www.ebay.com/itm/Camera-shutt...item230a1554f6

    This actually uses a photodiode to detect the increase/decrease in the amount of light, THEN converts that into sound waves sent to the computer. With this I can measure up to 1/250s reliably, and pretty good at 1/500s. The specs say it can do 1/1000s, which I'm finding hard to do. Regardless, you really can't beat the price

  6. #6
    cliveh's Avatar
    Join Date
    Oct 2010
    Shooter
    35mm RF
    Posts
    2,728
    Images
    336
    Quote Originally Posted by Mainecoonmaniac View Post
    I have the Shutter Speed app for iPhone and I find it hard to use. Maybe someone can make an app that uses the camera that actually measures the shutter with the camera by measuring duration of the light instead of using the sound of the shutter?
    Wash your mouth out with soap and water.

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon



 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin