http://www.nikonchat.com/dx-nikkor/
What is the difference between the Nikkor lenses and DX format FX format?
Thanks in advance
What it means is that the lenses DX are made for use with cropped APS-C, as in many nikon digital slr, such as D3100, D5100, D7000, D90, D300 … Not that big of a cast FX image as lenses, which project an image large enough to cover the full frame sensor, as found in the D700 and all of the D3 series. Can using a FX lens on any Nikon digital SLR without any problems. If you think you may want to upgrade to full-format camera, one day, you may you want to limit your glasses back to the FX format. You can probably use a DX lens on any Nikon digital SLR camera, too, but I'm not positive about this. The newer cameras is that it has set up a DX lens and automatically limits the size of the image to something like 5 megapixels instead of what could shoot camera with a lens on FX.
Nikon D5100 Test with AF-S DX NIKKOR 55-300mm Lens
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