I did not know this ( VR activation)

Discussion in 'Nikon' started by c.p.m._van_het_kaar, Nov 16, 2014.

  1. This Nikon article explains to me; some possibly unexpected unsharpnes in some shots when using AF-ON for focussing
    If VR is not fully stabilised yet when taking the shot itsometimes causes some unsharpnes, now if VR only kicks in when preesing the shutter release VR may not Always have fully stabilized yet in some cases because of this ?
  2. I think what the article is saying is that AF-ON and VR are separate systems such that if you use AF-ON to pre-focus, you should simultaneously activate VR by half-pressing the shutter as to allow it time to stabilize.
  3. Michael, the general idea using af-on for focussing assignment is that you do not have to half press the shutter release and take away the focusing activation from the shutter button. this is convenient when yuo want to pre-focus at a certain point , and take the shot when the subject enters the focussing zone quickly because no more foccusing is needed, by fully pressing the release at once.
    Now , as i understand it, chances are tht the VR in this case could affect the sharpness of the shot when not fully settled...
    BTW : I like your "Portraits of a Willow" a lot for there tranquil atmosphere !
  4. C.P.M., the VR has its own time constant which begins at the half-press so the image will not have time to stabilize if the shutter is full-pressed rapidly. It would be helpful if Nikon publishes a timing chart to show the various events' time constant.
    Re: Willows; one of my favorite subjects to shoot! Thanks!
  5. In at least some of the newer cameras (2012+; e.g. D800, D810, D4, D4s), the VR system is activated even when just the AF-ON is pressed, without touching the shutter button. In any case, using the older cameras, I would hold the shutter button half-way when I was getting ready to shoot so the VR had plenty of time to stabilize.
    But still, if you're critical, you may notice that the best sharpness of a lens is not achieved using VR, but a tripod and/or a fast shutter speed. VR has finite precision and in some circumstances it can actually add blur to the image. In my experience VR is most useful at mid telephoto focal lengths (i.e. 200mm) when hand holding the lens at shutter speeds of 1/FL and slightly slower speeds (i.e. 1/50s to 1/320s). At very fast shutter speeds (1/1000s etc.) VR has been reported to actually cause uneven sharpness in bands across the direction of the movement of the shutter curtains, so it is probably best left off in these situations, though it depends on the lens, how likely this is to happen. At very slow shutter speeds (1/25s, slower) although VR improves hand-held sharpness, it is unlikely to yield a really good result even so. Due to the probability of subject movement blur I rarely hand-held a lens at 1/100s or slower, if there are people in the frame. So that leaves a window between approximately 1/125s and 1/250s where there can be substantial benefits from the use of VR in hand-held telephoto use on people subjects (and others who can move). At high speeds one is probably best off just relying on the high speed to take care of movement and at really slow speeds only a tripod and a static subject (+ in some cases EFCS) can guarantee good results, whereas with a subject that can move, one is best off if increasing ISO and aperture to get the shutter speed to an acceptable range. But others may have slightly differing experiences with VR. I tend to keep it off most of the time, unless I'm in the "sweet spot" shutter window for VR use.
    A separate issue is the case when the photographer intends there to be movement blur. In such cases, slow speeds can be used with a moving subject to achieve a controlled sense of movement. A tripod or VR can be used to stabilize other aspects of blur than the subject movement. However, I've never been any good at this technique. I've noticed that e.g. Bence Mate has used it excellently in bird photography. Richard d'Iansen noted that this technique should be practiced whenever there is opportunity (since it's so difficult to learn how to do it well).
  6. Nikon's VR has different operation modes for aiming (triggered by the half-press and probably also AF-on) and for the actual exposure. Mind the active element is re-centered just prior to the exposure, and this move is supposed to settle in the short time before the shutter opens. There is a chance that this behaviour causes some blur, especially if the system happens to get detuned somehow.
  7. it looks like as if the view finder just got shaken, a small bump if you will. then the image is stable :)
  8. Nikon Europe has removed the article - apparently they got wind that it's somewhat outdated.
  9. I'm gonna have to try using AF-ON. Changed the settings and will see how I like it.

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