Page 1 of 5 123 ... LastLast
Results 1 to 10 of 49

Thread: High shutter speed accuracy?

  1. #1

    Join Date
    Jun 2006
    Location
    New Jersey
    Posts
    932

    High shutter speed accuracy?

    I got a Calumet shutter test, just testing a few shutters.
    I found between 1 and 1/60 most reading are within 1/6 stop but when I hit 1/250, or 1/400 the reading is way off. Is that because of the shutter or the shutter tester?

  2. #2

    Join Date
    Sep 1998
    Location
    GA
    Posts
    12,883

    Re: High shutter speed accuracy?

    A shutter is accurate if it is 30% of the marked speed. Except for a shutter like the Rollei Linear Motor electronic shutters most mecanical shutters: Compur, Copal, Prontor, Seiko, will be may be more then 30% at their fastest speed. This is true for these shutters regardless of the format used. In other words, a Hasselblad Prontor shuttered lens will be quite a bit off of a true 1/500.

  3. #3

    Join Date
    Jun 2006
    Location
    New Jersey
    Posts
    932

    Re: High shutter speed accuracy?

    If I shoot @ 1/500 I may have very good chance to have under/over expose my slides, is that right?
    BTW, I remember shooting 35mm format, there is a rule of thumb that if you hand held a camera the shutter speed should at least the inverse of the focal length of the lens. Does that hold for LF hand held cameras?

  4. #4

    Join Date
    Sep 1998
    Location
    GA
    Posts
    12,883

    Re: High shutter speed accuracy?

    Quote Originally Posted by Songyun View Post
    If I shoot @ 1/500 I may have very good chance to have under/over expose my slides, is that right?
    BTW, I remember shooting 35mm format, there is a rule of thumb that if you hand held a camera the shutter speed should at least the inverse of the focal length of the lens. Does that hold for LF hand held cameras?
    over. The shutter will not get to 1/500.

  5. #5
    hacker extraordinaire
    Join Date
    May 2009
    Location
    North Carolina
    Posts
    1,330

    Re: High shutter speed accuracy?

    Keep in mind that most leaf shutters will measure significantly slower than their "effective" speed even when they are in adjustment. A 1/500 shutter can be expected to measure 1/400 or less when tested with a shutter tester--this does not mean it is 'running slow' because it takes a finite amount of time for the leafs to fully open and close. This is compensated for with a slighly longer open-time. With leaf shutters at high speeds, shutter speed is also a function of aperture.

  6. #6

    Re: High shutter speed accuracy?

    Kentucky windage.

  7. #7

    Join Date
    Jun 2006
    Location
    New Jersey
    Posts
    932

    Re: High shutter speed accuracy?

    Quote Originally Posted by BetterSense View Post
    Keep in mind that most leaf shutters will measure significantly slower than their "effective" speed even when they are in adjustment. A 1/500 shutter can be expected to measure 1/400 or less when tested with a shutter tester--this does not mean it is 'running slow' because it takes a finite amount of time for the leafs to fully open and close. This is compensated for with a slighly longer open-time. With leaf shutters at high speeds, shutter speed is also a function of aperture.
    in high speed situation
    the smaller aperture, the slower shutter speed?

  8. #8
    Drew Wiley
    Join Date
    Sep 2008
    Location
    SF Bay area, CA
    Posts
    13,883

    Re: High shutter speed accuracy?

    I've had very good luck with the Calumet tester, both for large format lenses and small
    cameras. The readings reflect real world film testing. Every single Copal shutter I've
    tested, new or old, was way off at the highest speeds. But I've had Compur shutters
    which were spot on, even for analagous focal lengths, but otherwise hated because of
    their higher vibration. I came to the conclusion that most of this is in fact due to the
    respective shutter designs. Almost no one uses the higher speeds with a view camera
    anyway, and if they do, a strobe is probably involved and will be the primary determinant of the exposure anyway. I carry a tally of all my shutters, and would
    consider anything a third stop off to be of consequence with color tranny film. About
    once a year I retest each lens I frequently use. They don't seem to vary much with
    age.

  9. #9

    Join Date
    Dec 2001
    Location
    NJ
    Posts
    7,621

    Re: High shutter speed accuracy?

    Quote Originally Posted by Songyun View Post
    in high speed situation
    the smaller aperture, the slower shutter speed?
    No, its the other way 'round.

    If you want to know whether a shutter will overexpose, shoot reversal film with it.

  10. #10

    Join Date
    Jan 2009
    Location
    Waynesburg, PA
    Posts
    56

    Re: High shutter speed accuracy?

    Are you using the Calumet instructions, especially important for the higher shutter speeds?

    --
    Alan

Similar Threads

  1. Shutter Speed Check...
    By Kuzano in forum Lenses & Lens Accessories
    Replies: 8
    Last Post: 5-Feb-2009, 20:31
  2. shutter speed test
    By Joseph O'Neil in forum Lenses & Lens Accessories
    Replies: 3
    Last Post: 27-Nov-2008, 09:54
  3. 8x10 lens with 1/500th shutter speed ??
    By chris jordan in forum Lenses & Lens Accessories
    Replies: 25
    Last Post: 26-Nov-2004, 17:06
  4. Shutter Speed Calibrating
    By Rob Hale in forum Lenses & Lens Accessories
    Replies: 6
    Last Post: 28-Aug-2004, 04:12
  5. Speed Graphic shutter curtain travel time
    By Erik Ryberg in forum Cameras & Camera Accessories
    Replies: 3
    Last Post: 13-Aug-1998, 18:01

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •