Looking for a lens

[A340_flyer]

I have a D70 and use a Nikon 70-300mm F4-5.6 G lens for my long range shots. It's a decent lens but as with all entry-level lenses it's limited. I'm looking at upgrading lenses to something that firstly produces sharp pictures (obviously), still works well at ranges of about 300mm, and has a fast autofocus. I'm not really in the know when it comes to lenses so any help would be greatly appreciated. Are there any particular lenses which work well with a teleconverter?

I recently read a few reviews on the Nikon 80-400mm F4.5-6.3 VR ED lens and some have said it has a slow autofocus. Is this true? How does it measure up to a lens like its counterpart the Canon 100-400mm L IS lens (if they can be compared)?

The other lens I have is the standard Nikon 18-70mm F3.5-4.5 ED lens which I'm quite happy with.

Thanks!

[seahawk]

Hmm, the 80-400 VR is a slow lense compared to the other professional line Nikors. Especially the AF-S versions. However I have seen many spotters using it quite happily. And doing aviation you are mainly foccusing near infinity so the focus is not that hard pressed.

A good alternative is the sigma 100-300 HSM. I have heard many good comments about that lense.

Another interesting alternative, but much more expensive would be the Nikon AF-s 70-200 2.8 and the TC-17E converter from Nikon. That is a nice combination, but about 50% more expensive then the 80-400.