http://www.nikonchat.com/dx-nikon-d-slr/
nikon lens questions please help?
http://www.amazon.co.uk/Nikon-AF-S-70-300-4-5-5-6G-IF-ED/dp/B000HJPK2C/ref=sr_1_1?ie=UTF8&s=electronics&qid=1237805345&sr = 8-1 looking at achieving this goal. I have a Nikon D40 which is a DX model. they say that if you use this lens for this model offers a 4.3x zoom with a range of 70-300mm (105-450mm on a DX Nikon D-SLR), 'Why is the range of 105-450 in the DX? And is there much difference to focal range. It's because the camera is not full frame?
Your camera, with its small sensor, has what is called crop factor. "What this does is reduce the real viewing angle of any target used. A 70 mm lens on a 35mm camera or full frame sensor DSLR-would have a viewing angle of 34 "20 '. In a sensor" cut "His camera like the D40 70mm lens will have a viewing angle of 23" 20 ", which is equivalent to a 105mm lens on a full frame sensor. In other words, the wide angle is not as wide.
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