I am new to SLR and had just bought a D5000 that comes with a AF-S DX NIKKOR 18-55mm f/3.5-5.6G VR (3.0x) lens and what does the f/3.5-5.6G mean?
18-55 equates to 27-82.5mm on your camera because of the sensor-crop. [URL Truncated]
f/3.5 - 5.6 means the maximum aperture at the 18mm end is 1/3.5 of the focal length and 1/5.6 of the focal length at 55mm.
Aperture, by the way, is the hole created in a lens by the diaphram blades - the larger, generally speaking, the better. A large aperture has a small number (it's a mathematical thing - simply the lens' focal length divided by the hole diameter) and, therefore small apertures have larger numbers. This restricts the amount of light entering a camera.
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Just say you had a lens with an aperture of f/1 (a 50mm lens would therefore have a 50mm aperture) and it allowed x amount of light through. Close that aperture to f/3.5 and you'd be restricting the amount of light by that amount:- x/3.5. Apart from helping the camera get correct exposures, it's useful for creative control of the depth of field.
[URL Truncated] - read it thoroughly and you will learn more than what I can type here.
G is simply Nikon's terminology to describe a lens that doesn't offer manual aperture control, a more comsumer-orientated lens, distinct from their D series.
f/3.5-5.6 usually means that at the short end of the zoom in this case the 18mm (wide angle) the effective f/stop or lens speed is f/3.5....... And at the long end of the zoom in this case 55mm ( "telephoto") the effective f/stop becomes f/5.6.
Therefore the lens is "slower" (in light-gathering ability) at the longer end of it's zoom (55mm)
So what does this all mean to you? Well simply put the manufacturer of the lens can make the lens smaller physically, making the camera lighter and easier to carry, hence more attractive to purchase.
Now what does the designation"G" mean, tacked on to the end? I, frankly don't know, but I would presume it has to do with our "digital age" designations verses "film" designations.
"newer AF G-series Nikkor lenses now has NO aperture ring on the lens barrel for controlling aperture"
Apparently you cant manually set the aperture on the AF-G series Nikon lenses
3.5-5.6 is 3.5 aperture at 18mm and 5.6 aperture at 55
Pretty slow lens for 18-55 range
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