Nikon maintains DSLR lead over Canon

Discussion in 'Nikon' started by frederick, Jul 13, 2007.

  1. In other words, IS/VR adds absolutely no real word benefit to WA lenses.
    This leads me to part two of the problem. On WA lenses the optical element
    needed for IS/VR correction is not designed to deal with barrel distortion
    and other optical problems. After considering all the pitfalls and
    *minimal* perceived benefits from IS/VR, the lenses manufacturers concluded
    that it is technically and financially impossible to make a WA pro lens with
    IS/VR. That said, we will never ever see a pro prime lens of 50mm and wider
    with IS/VR.





    Rita
     
    Rita Ä Berkowitz, Jul 19, 2007
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  2. frederick

    Sachin Garg Guest

    I am kinda surprised that tables turned so fast, it will be
    interesting to see if global figures follow same trend :)

    Thanks for the link.

    Sachin Garg [India]
    www.sachingarg.com | www.c10n.info
     
    Sachin Garg, Jul 19, 2007
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  3. frederick

    SMS Guest

    Not surprising given Nikon's intro of the D80 and D40/D40x. Canon's 400D
    falls short of the D80 in several ways, and Nikon's D40/D40x are at a
    price point where Canon really has no competing product. Similarly, the
    D200 beats the 30D in several ways.

    Canon really needs to address the low to mid-range of the D-SLR lines.
     
    SMS, Jul 19, 2007
  4. But the geometry of the optics doesn't change, and there are huge
    differences as a result of that. How close the object is matters as
    well. For example, think of taking a macro shot. Shifting the camera
    0.1mm vertically upwards will have a very large effect compared to the
    negligible effect of shifting vertically upwards 0.1mm when
    photographing a landscape. In the case of the landscape, and in
    general, rotational movement is by far the most important. A very
    small shift in the direction the camera is pointing will have a large
    effect on the image.

    Suppose for example you're using a lens with a field of view of 30
    degrees, and suppose you wish to produce an image which is sharp at
    300 ppi on a 10 inch wide print. The span of your field of view is
    divided into 3000 pixels. So a rotational shift of 30/3000 = 1/100th
    of a degree will move the image over one pixel, and you'd probably
    have to hold it to within 1/1000th of a degree to keep the softening
    of the image due to shake negligible.
     
    Chris Malcolm, Jul 20, 2007
  5. It depends on the parameters of the IS, how it was designed, what it
    was designed to do. Firstly it can only move so much before it hits
    the edge. Secondly it has to ignore slow speed drifts otherwise it
    will hit the edge when you move the camera to look at something else
    and not recover before you've pressed the button. In other words there
    will be a shutter speed below which it won't work, and that will
    depend on its design.
     
    Chris Malcolm, Jul 20, 2007
  6. frederick

    Jeremy Nixon Guest

    There is "getting away" and then there is "getting away". With a wide
    angle lens, at 1/125, using a tripod still makes a difference, if you're
    enlarging enough. At 1/10 it makes a *big* difference; even if the
    hand-held shot looks sharp, the tripod shot is sharper.
    Why do you assume there must be any? Rita doesn't know what he's talking
    about. (And is most certainly not female.)
     
    Jeremy Nixon, Jul 21, 2007
  7. Fair enough comment - I don't do very big enlargements.
    I didn't assume - I said "might".

    David
     
    David J Taylor, Jul 21, 2007
  8. If you quantify them as I did above then roll about the axis of sight
    has far less effect than yaw and pitch on the image. It has comparable
    effects to linear position shifts.
    It's not difficult to bound it with reasonable general maxima and
    minima. Note too that for a given shakiness and strength of hands,
    then the heavier the camera the more slowly it will move, up to a
    maximum which is probably heavier than any hand-held camera unless
    you're pathologically weak or shaky.
     
    Chris Malcolm, Jul 21, 2007
  9. frederick

    Neil H. Guest

    Sure, but what I'm wondering about is the relative effects of the three axes
    of rotation. I think that yaw and pitch would have the greatest effects on
    blur, and roll would have much less. But how to quantify them?
    That's an interesting way of looking at it, but I'm not sure how useful it
    is. In order to translate any of that into required shutter speed you'd have
    to know the *speed* of camera movement (i.e., angular velocity) as well.
    That I think would be difficult to arrive at, with the movement in human
    hands.

    Neil
     
    Neil H., Jul 21, 2007
  10. frederick

    RichA Guest

    As anyone who shoots a gun can tell you, there is a vast difference in
    movement characteristics depending on how you control things like
    breathing, your stance, you hand position on the camera/lens, etc.
    Consistency is the key, once you've isolated all the variables.
     
    RichA, Jul 21, 2007
  11. I show a way how to compose w/o stopping down and you want to
    saddle me with non-cpu nikkors and no D200 --- which, being a
    Canon user, I have no need for?

    -Wolfgang
     
    Wolfgang Weisselberg, Aug 10, 2007
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