AF or AF-S on a Nikon D5000?

I'm wanting a good (but relatively cheap) telephoto lens for my Nikon D5000 for wildlife photography. The lens in question is a Nikon 300mm /f4.AF. What's the difference between AF and AF-S besides being silent? Does it impact the image quality if i use an AF vs an AF-S? The AF is so much cheaper. And if you know of any better and cheapish lenses, please let me know!

AF-S lenses have a focus motor in them.

The D5000 doesn't have a focus motor in the camera body, so if you want autofocus, you NEED AF-S lenses. If you use AF lenses, you will have to manually focus them on your camera.

Edit: The "S" in AF-S stands for "silent wave", Nikon's terminology for an ultrasonic motor.

There are a few ways to look at this situation

* you could save money and buy the Nikkor AF lenses and take the time to learn how to manually focus (an excellent skill by the way)
* or you could just save your pennies until you can afford the AF-S lenses.

All the AF-S lenses auto focus faster than the older AF, when used with more advanced Nikon bodies like the D7000 and up.

What that means is if you can take the time necessary to have the budget to buy AF-S lenses, you will be able to shoot action and sports and use the technique called follow focus automatically

Only AF-S and AF-I will autofocus with your camera.AF only won't.

http://www.kenrockwell.com/...s.htm#dslr

It has something to do with the missing AF motor in your camera.AF-S and AF-I lenses have their own motors.

The AF lens won't autofocus. Nikon is on the way to phasing out AF lenses (by eliminating in-body focus motor from their cameras) too, so they're a poor investment.