Vr nikon how does it work




















In almost all of those cases I've been able to find that it's not VR itself that's helping remove camera motion, but that their handholding or tripod technique is such that they're not getting consistent autofocus without VR, but they are with it.

However, as with virtually everything in photography, there's a caveat to the above. One of the things that Nikon just doesn't explain well enough is the concept of "moving camera" versus "camera on moving platform. However, if there's a platform underneath you causing vibrations car, boat, train, plane, helicopter, etc.

Active VR should be used when you're on one of those moving platforms. Normal VR should be used when you're on solid ground and it's just you that's shaking. Basically, if you're vibrating due to outside source, Active VR should be On. If you're the only source of camera movement, then use Normal. The difference between Active and Normal VR modes has to do with the types of movements that are expected and which VR will attempt to correct.

Handholding motion tends to be slower and move in predictable paths e. Knowing which type of motion the VR needs to deal with lets the system optimize its response. The motion that you impart by your handholding may not get corrected right by the VR system because your shutter speed is faster than the frequency with which corrections are well managed.

But the platform you're sitting on is imparting small, frequent, and random motions that might actually be corrected but probably not fully by having VR on. The question here is whether the improvements due to removing some of the platform movement are better than the possible degradation due to the shutter closing faster than the VR is working.

There's no clear answer to that, as every situation is going to be a little different, but my tendency is to experiment with Active VR being On versus VR being totally off when shooting from moving platforms at high shutter speeds. I closely examine my initial results, and make my final decision based upon that. Of course, that in and of itself can be a problem for some, as examining a small screen in a moving vehicle isn't exactly easy and precise. Still, I sometimes see an improvement with VR as opposed to without it when I'm shooting at high shutter speeds from a vehicle.

At the same time, that's not as much improvement as you'd see using a dedicated gyroscope instead of VR. If you regularly shoot out of helicopters, a gyro is a better investment than a more expensive VR lens. Some explain that shutter speeds above that are done by moving an opening across the image rather than having the full image exposed simultaneously this is a simplification, but it's good enough for this discussion. Nikon claims that they now can distinguish between camera movement and platform movement based upon the information the gyros are providing the system.

In such cases, turn off Sport VR and use Normal if you're on an active platform. At the other end of the movement spectrum, we have subject motion. If the subject is moving, using VR with longer shutter speeds can be problematic. This is a tough thing to learn, and it's usually learned the hard way. But the only motion being removed by the system is camera motion. This is, of course, a generalization. There's a more detailed table below the one I just referenced that shows how distance impacts the shutter speed, too.

Plus the size of the subject in the overall frame makes a difference. Expecting VR to remove all motion including subject motion is something everyone has to get over:. Another type of motion comes with panning the camera, and VR has impacts there, too.

I've seen people say that they think you should turn VR off when you pan with a subject. That's because the Nikon VR system is very good about detecting a constant camera movement. If you're doing a smooth pan in one direction, the VR system will focus on removing only motion on the opposite axis. That's the way it's designed to operate. The trick is to make sure that your pan is relatively smooth, and not jerky. Most people start to jerk when they press the shutter release during pans.

You need to practice NOT doing that and to continue the pan while the shutter is open, not stopping. Indeed, try practicing this at your local track or other place with some runners present. Pan with the runner and take a picture. When the mirror returned and the viewfinder view is restored after the shot is the runner still in the same spot in the frame? Then you didn't continue panning through the shot.

Tsk tsk. Try again. Practice until you can take a series of shots and the runner stays in the same spot through the entire sequence, both in the shots and while you're panning between shots. You shouldn't be having to catch up to the runner.

Aside : Back in high school my photography mentor at the time broke me of the habit of stopping during pans in a brutally sadistic way: he sent me to track meets with a TLR twin lens reflex. You look down into the viewfinder of a TLR. But here's the thing: left to right is reversed. So if the subject is moving right to left in front of you, they appear left to right in the viewfinder. You don't have a chance of following motion with a TLR unless you can relax your brain and make your camera motion just mimic the motion of your subject.

You can't look and react, look and react. Yet another aspect of VR that confuses people is activation. A partial press of the shutter release always engages VR and allows it to begin a sequence of corrections. Basically, if you engage VR prior to the shot, you tend to get slightly better and more consistent results.

That doesn't mean you should always wait for VR to engage before fully pressing the shutter release. If it's time to take the picture, take the picture! VR will give you its best shot at fixing your camera motion when you just punch the shutter release. But there are two factors that tend to make early VR engagement a better choice if you can do it: first, the VR system gets a stream of data it can predict from; and second, it's difficult to move the camera as much by jabbing the release if you've already partially pressed the release!

The usual issue that comes up with the last paragraph is the line in many Nikon's manuals about "VR doesn't function when the AF-ON button is pressed.

Only the shutter release button engages VR on earlier cameras such as the D3 and D Thus, if you use AF-ON to focus instead of a partial shutter release, VR is not engaged during the pre-shot focusing for those cameras. But it is during the shot. See note at very bottom of article. This, of course, creates a slight issue.

If we're using AF-ON to focus, our fingers usually aren't pushing the shutter release partially down, too. That right hand is starting to do a pretty complicated dance: AF-ON up and down for focus, shutter release partially down for VR, right thumb dialing in shutter or aperture or exposure adjustments, maybe right middle finger dialing in aperture adjustments, shutter release fully down with the index finger for the shot. This, by the way, is one of the reasons why I prefer Nikon's ergonomics to Canon's: at least when I'm doing all that hand juggling, my hand and finger positions aren't really moving, especially my shutter release finger.

With Canon the tendency is to move the index finger between the top control wheel and shutter release. You can react with the shutter release faster if you're not moving that finger.

There are a few more caveats. If you've got a built-in flash on your camera basically everything but the D1, D2, D3, D4 D5 series, and the D and D , while the flash is recharging the VR system is inactive. That's because VR takes power to perform and the assumption is that you want the flash recharged as fast as possible.

Thus, the camera turns off the power to the VR system while it's charging up the camera's flash capacitor. If you're shooting flash near full power and doing a lot of consecutive flashes, the flash recharge time can start taking a few seconds.

How do you know if power is restored to the VR system? Well, you can't, exactly, but the flash indicator in the viewfinder is a fairly reliable indicator: if it's not present with the flash up and active, VR is probably Off. I've been holding off on the tripod issue to the end of this article, partly because it's not as clear cut as Nikon seems to think it is. Part of the problem is that Nikon hasn't clearly labeled and described their various VR system iterations.

Technically, the VR II system on some of the modern lenses should detect when the camera is on a stable platform and not try to jump in and correct anything. But not all modern lenses have what most of us regard as the full VR II. The recently introduced mm, for example, comes long after the intro of VR II, but it does not appear to have tripod recognition.

Thus, we have another rule before we get to the real rule:. Rule 8 For Real: If your camera is on a tripod, even if you're using something like a Wimberley head where it is almost always a bit loose, just try turning VR off. So why do I disagree with Nikon?

Even with a loose head on a tripod, motion should be fairly easy to control, and you should have removed one possible motion almost completely ditto with monopods. The problem I have, and which many other pros have noticed, is that the VR tripod detection system sometimes produces "false negatives. Most of the time it does just that Nikon says that the current system is smart enough to detect as many as three different types of motion—handholding, platform vibration, and support system movement—because the "vibrations" caused by each of these are recognizably different in wave form.

Every now and then, though, VR thinks it needs to correct when it doesn't or perhaps is still correcting for a previously detected motion that will no longer be present in the next sampling. When that happens, the VR element s are moving when they shouldn't be.

Usually not a lot, but enough to make for less than optimal results. The advantages of VR and IS, is that you can achieve sharper photographs when hand holding your camera, especially in darker lighting. For example, sporting events, museums or photographing moving animals like birds or fish.

Those who have tried to photograph a flying bird while their camera sits on a tripod will understand the frustration.

Vibration Reduction VR is an image stabilization technology that minimizes blur caused by camera shake. The value is achieved when a DX-format compatible lens is attached to a DX-format D-SLR camera and zoom lenses are set at the maximum telephoto position or when an FX-format compatible lens is attached to an FX-format D-SLR camera and zoom lenses are set at the maximum telephoto position.

Nikon VR originates in the lens, not in the image sensor, which means that algorithms optimized to an individual lens are applied. Another advantage of lens-based VR is that a separate algorithm confirms the stabilization effect when you press the shutter release button halfway, giving you the freedom to compose your image more easily.

Nikon VR lenses use two angular velocity sensors, one that detects vertical movement pitch , the other, horizontal movement yaw , with diagonal motion handled by both sensors working together. The sensors send angular velocity data to a microcomputer in the lens, which determines how much compensation is needed to offset the camera's shake and sends that information to a duo of voice coil motors that move selected lens elements to compensate for the detected motion.

What does this mean in practical terms? It provides you with up to four stops of "hand-holdability," delivering dramatically sharper images in a wide range of conditions. Not all anti-shake technologies are the same. The in-camera anti-shake technology used by some manufacturers relies on a process that actually shifts the image sensor, and its performance benefit is generally agreed to be limited to about one-and-one-half to two stops.

For Nikon photographers, an additional two stops of VR performance capability can easily be the difference between a blurry picture and a beautiful sharp one. But the benefits of Nikon VR aren't limited to shutter speeds.



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