http://www.nikonchat.com/lens-nikkor-70-300mm/
How do I use the autofocus on a nikon d40x with Nikkor lens f/4-5.6G-300mm 70?
I just bought a Nikon Nikkor 70-300mm f/4-5.6G and it seems that I can use the autofocus function. Please provide detailed instructions because I am a beginner. Thanks!
A less than 70-300 mm lens is the AF-S model, you need to use the electronic rangefinder and manually focus the lens. Nikon's entry-level dSLR autofocus only with AF-S and AF-I Nikkor lenses. This is how Nikon could sell cameras at a price so low no onboard autofocus motor in the camera. The good news is twofold. 1) AF-S lenses are the fastest autofocus in the world right now and 2) a manual focus lens is Pentecost photographers did all the time until about 30 years ago when some cameras offer auto focus camera and lenses. Manual focus will target a more disciplined shooter
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