Image stabilization shoud be stabilized

Discussion in 'Photography' started by PeterN, Aug 17, 2013.

  1. PeterN

    Eric Stevens Guest

    So you are ignoring the reports and the technical analysis which shows
    that under the right image stabilisation *can* lead to the image
    moving on the sensor.

    I presume you have no evidence to contradict the claim.
    So now, you are agreeing with what Peter and I wrote.
     
    Eric Stevens, Aug 18, 2013
    #21
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  2. PeterN

    Guest Guest

    i'm not ignoring it all. i explained why it can happen and when.

    why do you ignore that?

    in normal use, stabilization *reduces* the amount the image moves on
    the sensor. that's the whole point.

    outside of that, pretty much anything goes.
    contradict what claim?
    partly.

    i said there's an issue at high shutter speeds but *not* because it
    affects autofocus. it's the stabilization sampling frequency.
     
    Guest, Aug 18, 2013
    #22
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  3. PeterN

    Sandman Guest

    Is this really news?

    "There are a number of folks out there, who seem to think that just
    firing the shutter button is sufficient and that VR will stabilize
    those images as good as if one were to half-press the shutter
    button, wait a few seconds and then take an image"

    Really? Who are these people? Anyone that have used IS should have
    noticed the difference between direct release and waiting for the IS
    motors to do their job.

    Now, had he said that "a number of folks out there hasn't *realized*
    that the IS motor needs a second to stabilize the lens.." then I
    wouldn't disagree, but I find it hard to believe that there are users
    who have shot with and without direct release and still argue that IS is
    better, or as good, with direct release.
     
    Sandman, Aug 18, 2013
    #23
  4. PeterN

    Sandman Guest

    Not really. The images are so heavily post processed and JPG compressed
    that it's hard to see the original difference. Of the four, the last
    with VR on is by far the most sharpest, but it too has a lot of post
    done to it.
     
    Sandman, Aug 18, 2013
    #24
  5. PeterN

    Eric Stevens Guest

    Because we were discussing your no doubt correct claim that image
    stabilisation can assist auto focus in the right circumstances.
    Where all this started: the claim that image stabalisation can lead to
    focus (Note: NOT autofocus) problems at high shutter speeds.
    But *nobody* made the claim that it was because of interference with
    autofocus.
     
    Eric Stevens, Aug 18, 2013
    #25
  6. PeterN

    Guest Guest

    it helps autofocus in just about every circumstance because the subject
    isn't moving as much so the focus points stay on the same parts.
    it has no effect on focus at any shutter speed. how could it?

    the problem is when using a shutter speed that's faster than the
    sampling rate of the stabilizer.

    focusing is completely irrelevant, auto or manual.
    peter's link said this:

    <http://www.evergladesphotosociety.org/articles/flightpart01.html>
    If your camera has built in Image Stabilization (IS) you¹ll want to
    turn it off. Image Stabilization (IS) is a feature that helps the
    user take pictures in low light with slow shutter speeds. At a
    shutter speeds above 1/500s, IS only serves to slow down the camera¹s
    autofocus speed.

    that statement is not only false, but absurd. stabilization *helps*
    autofocus, regardless of shutter speeds. in fact, the autofocus system
    doesn't even know what the shutter speed will be! nor does the
    photographer if the camera is in p or a modes.
     
    Guest, Aug 18, 2013
    #26
  7. PeterN

    Ghost-Rider Guest

    Le 18/08/2013 12:31, nospam a écrit :
    I always use IS for my macro shots of insects with my Nikkor 18-300.
    As, considering the low angle of the lens, I tremble a lot, IS enables
    me to keep the focus point on the eyes which is of a paramount
    importance due to the very small depth of field.
    http://cjoint.com/13au/CHso3vDPXCy_d7000_07777-002.jpg
    Heavily cropped : 30%
     
    Ghost-Rider, Aug 18, 2013
    #27
  8. PeterN

    PeterN Guest

    Nope. Nikon has focus tracking
     
    PeterN, Aug 18, 2013
    #28
  9. PeterN

    PeterN Guest

    Good seeing.
    I agree that VR is great for hand held macro. For most my my macro
    shots, I do not use autofocus. I like to control where the sharp spot on
    my image will be.
     
    PeterN, Aug 18, 2013
    #29
  10. PeterN

    PeterN Guest

    Sounds like you and i are in total agreement on the main issue. Image
    stabilization takes a period of time to stabilize.
    I really don't have a need to analyze his words as you do. I simply
    posted what works for in flight bird photography.
     
    PeterN, Aug 18, 2013
    #30
  11. PeterN

    PeterN Guest

    Not really a lot of post.
    Aside from a bit of NR and contrast adjustment, with the hummer I played
    with color adjustments to cut down highlights in the plant.

    With the osprey, I put in the cloudy sky. and some sharpening

    The anhingha was sharpened, and some color adjustments made to bring up
    the green in hte branch he was carrying.

    I do not call that a "lot of post."
     
    PeterN, Aug 18, 2013
    #31
  12. PeterN

    Eric Stevens Guest

    I should have written 'image sharpness'.
    The ultimate question is whether or not the use of stabilisation
    results in a better image. For reasons of which you seem to be well
    aware, the answer appears to be 'not always'.
    Read what he wrote. Peter wrote about "the camera's autofocus speed",
    not the autofocus accuracy. Depending on the camera it is conceivable
    that the to-ing and fro-ing of image stabilisation may cause the
    autofocus to take longer to decide upon a proper focus than if the
    image was not stabilised.
     
    Eric Stevens, Aug 18, 2013
    #32
  13. PeterN

    Eric Stevens Guest

    On Sun, 18 Aug 2013 15:07:24 -0400, PeterN

    -- snip ---
    I wasn't talking about the image moving in and out of focus. I was
    referring to the image moving _across_ the sensor while the image
    stabilisation is in the process of catching up with your camera shake.
     
    Eric Stevens, Aug 18, 2013
    #33
  14. PeterN

    Savageduck Guest


    Well, your "not really a lot of post" and somebody else's are probably
    a little different
    The big problem with those samples is the jpeg compression and
    variation in size. So, making a comparison for sharpness/focus is tough.

    The Osprey, while being a great capture, has all sorts of issues which
    ruin the image for me. I have a shopping list of issues none of which
    have to do with focus or camera shake. At least you have it at a decent
    size.

    The Anhinga has focus issues, there is nothing in focus. Whatever you
    did in post has left a halo around the entire bird. There is no way of
    telling what the cause of the focus issue is. I doubt that having the
    VR off is an issue since it looks as if you might have been panning,
    and shooting at 1/800, f/8, and even at ISO 6400 it should have been
    sharp. I suspect you have done something to blur the background to
    emphasize the bird, as the background should not appear the way it does
    at f/8, 1/800. Unfortunately it is a not savable image of a timely
    capture.

    A hummer is always tough to capture and this one is no exception, and I
    think your biggest issue is the f/32 which has pushed the shutter speed
    to 1/250. At f/8-f/12 you should have a much faster shutter speed and
    a sharper capture.

    The Oyster catcher is the best of the bunch, but the crop cutting the
    reflection spoils the composition a bit. Then your resizing and jpeg
    compression makes it ordinary for the online viewer.
     
    Savageduck, Aug 18, 2013
    #34
  15. PeterN

    Sandman Guest

    Sounds like you and i are in total agreement on the main issue. Image
    stabilization takes a period of time to stabilize.[/QUOTE]

    No doubt!
    I'm not analyzing anything, I'm questioning his claim that there are
    people that believe that IS works as good on direct release as when
    waiting for it to engage...
     
    Sandman, Aug 19, 2013
    #35
  16. PeterN

    Guest Guest

    initially it does but once it stabilizes, there is no delay.
    it might work for *you*, but stabilization is *very* useful for bird
    photography as well as other types of photography, which is why
    stabilized lenses are so popular.
     
    Guest, Aug 19, 2013
    #36
  17. PeterN

    Guest Guest

    that's different.
    true, but for different reasons than was mentioned in the link.
    nope. stabilization *helps* autofocus speed for reasons i already gave.
    it does not slow it down. that's just nonsense.
     
    Guest, Aug 19, 2013
    #37
  18. PeterN

    Guest Guest

    some people don't understand how things work.

    one advantage of in-lens stabilization is you can see it working and
    can see it when it's stable.
     
    Guest, Aug 19, 2013
    #38
  19. PeterN

    Sandman Guest

    some people don't understand how things work.[/QUOTE]

    No doubt - but we're talking about people that would have to have
    compared the two scenarios and determined that it's better on direct
    release, which I find unlikely.
    Indeed.
     
    Sandman, Aug 19, 2013
    #39
  20. PeterN

    Eric Stevens Guest

    Let's say it takes time 't1' for the autofocus find the right focus
    point with an unstabilised lens. Also lets say it takes time 't2' for
    the stabilisation of a stabilised lens to settle down to stabilising
    the image. What happens if t2 > t1 ?
     
    Eric Stevens, Aug 19, 2013
    #40
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