Can a nikon d3100 mount all types of nikon lenses? If not then which once it won't support?
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plus what is "f3.5G VR." in a lense. How does its higher or lower value affect photographing?
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Nikon's Mount hasn't changed in nearly 60 years
here is a full Nikon camera compatibility chart
http://www.kenrockwell.com/...y-lens.htm" class='ext_link'>http://www.kenrockwell.com/...y-lens.htm
as for f3.5G VR
the f3.5 refers to the largest aperture, the smaller the number, the larger the aperture because it is focal length/aperture in mm
the larger the aperture, the more light let through the lens, therefore making it easier to shoot in low light condition. It also affects depth of field.
G refers to lens type, G is the newest lens type from Nikon.
VR refers to vibration reduction, which is Nikon's take on image stabilization
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Somebody correct me if I'm wrong, but I'm sure that all current Nikon lenses will work on a D3100, but only AF-S lenses can autofocus.
As for the "f/3.5G VR," f/3.5 is the maximum aperture, i.e. The hole in the lens that controls how much light can get through. The smaller the number, the larger the hole. For example, f/2 lets in a lot more light than f/11. Aperture also controls depth-of-field, which is generally what most people would call "blurring the background and keeping the subject clear," when in reality, the background is not blurry, it's out of focus. Apertures like f/2.8 generate a shallower depth-of-field (less in focus) as opposed to f/22 (more is in focus).
The G stands for Gelded. This link will explain that: http://www.kenrockwell.com/...rtek.htm#g
As for VR, that is Vibration Reduction. It helps keep your shots sharp by preventing small amounts of camera shake during hand-held shooting. Other brands have different names for this feature -- Canon calls it IS (image stabilization), Sony calls it Steady-Shot, Tamron calls it VC (vibration compensation), and so on.
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The short answer - All Nikon AF-S lens will auto-focus on your D3100. Virtually all Nikon mount lenses of any vintage will mount.
Here's a list of the Nikon and 3rd party lenses that are 100% compatible with your camera.
http://en.wikipedia.org/...cus_motors
F/3.5 refers to the maximum aperture of the lens. The lower the f/stop number, the more light the lens can capture.
G means that it's a Nikon lens that doesn't have a adjustable aperture ring, not necessary on current cameras as you control that via the command dial on the camera body.
VR means Vibration Reduction. Your lens has a built-in stabilizaton system that steadies the camera and lens, allowing you to shoot with less motion blur. With practice, it virtually replaces a tripod.
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The D3100 will mount any lens with a Nikon-F mount. Check this site for compatibility issues.
http://www.kenrockwell.com/nikon/compatibility-lens.htm
The larger the aperture size (lower f/number) the more light allowed inside the camera, the faster shutter speeds possible, making shooting in low light better and making blurred backgrounds easier.