piperknitsRN wrote:
Just curious. On my new Nikon 3100, there's a tab switch on the lens labeled "VR". I assume this means "vibration reduction," but I'm unsure when to use it/why I would need to use it.
Yes, "VR" means "Vibration Reduction" - Canon calls it "IS" for "Image Stabilization", other companies have different names for the same thing. What VR does is to sense tiny movements of the camera, usually caused by your hands shaking, and moves one element of the lens to counteract the movement.
You should
always use VR if you're hand-holding the camera. It will result in sharper pictures. This isn't theoretical - I've done actual tests with Nikon VR lenses (I have the 18-200VR and the 70-300VR) and with VR I can hand-hold the lens at much slower shutter speeds than I can without it.
The usual rule is to use a tripod if the shutter speed number is lower than the focal length of the lens. That means that with the zoom at, say, 200mm, you shouldn't hand hold at a shutter speed of less than 1/200th. The VR will give you two or three stops advantage (the book says four stops, but that might be pushing it for a newbie). This means you can safely hand hold at 1/60th or 1/30th. After years of practice I can do much better than the rule, but the VR still helps - when I first got the lens I tried taking a picture at 1/10th second with the lens at 300mm, and it was sharp. That's just incredible.
Ken Rockwell has a very good article on
why VR matters.
One point - if you're taking pictures from a moving car, be sure to put the lens in "active" mode, otherwise always use "normal".
That said, there's one time when you don't want VR - if you're using a tripod or have the camera on a beanbag - any situation where the camera isn't subject to hand vibrations - make sure you turn the VR off. Otherwise, the VR will get confused and introduce vibrations to overcome the movement the camera isn't making. Ken's article says he's never seen this effect, but I have, enough that I always turn VR off on tripods as the manual says to.
Don't be concerned about battery drain caused by VR. I use the VR all the time, and I still get way more than 1000 pictures on a charge on the D7000, closer to 2000 if I don't use the big LCD display much. The advantages of VR vastly outweigh a tiny fraction of decreased battery life.