Will the 300 f4 autofocus with anything over 1.4X teleconverter?

[viper_biker]

I was thinking of getting both a 1.4X and 2X T/C for my Nikon 300mm f4 AF-S (mounted to a D300) but I was told that it won't focus if the max aperture is above 5.6. Is that correct?

[purpleclouds]

I know that on Canon, only the 1D series will autofocus up to f8, perhaps it is the same with the Nikon range!

[puddleduck]

Is that correct?

No - who told you that? Find them now and point and laugh :)

It works fine and AF's with the 1.7x and 2.0x just fine.

[desantnik]

Nah, all of your 9 cross point focus points will focus up to F8.

From personal experience with the exact combo you asked about, it definitely works!

Its only those old Canon things that have a ceiling of f5.6 on anything but the 1D series.

[lammypaul]

well who wants to use anything but the 1d series, oh yes you lot.:lol:


cheers paul:thumbs:

[desantnik]

Meant to add though, you'll notice the 2x slows AF down big big big time though and anything but a nice clear bright sunny day will give you a lot of soft images.

[viper_biker]

Thanks for the replies. So the 1.7x would be better than the 2x for the obvious reasons. Next then, who do you give your money too? Sigma, Kenko, Nikon? Are they all pretty much the same resultsor are you really getting what you pay for?

[desantnik]

I'd go with the Kenko Pro 1.4x and the Nikon 1.7x (don't think anyone else makes a 1.7x)

The Kenko seems just as good as the Nikkon 1.4x and is about 140 quid cheaper!