Nikon vs third party autofocus speed.

[biotime_biotime]

I need to buy a standard and a tele-zoom for a Nikon F4.(28-78 and

70,80 -200+) I am only looking at 2.8 or close to them for the

quality. I think I would be happy optically with Tokina ATX pro used

for around 300.00. BUT. My big issue and the reason I went from

Pentax LX to Nikon f4 was for auto focus. From this site

http://www.photozone.de/bindex2.html it seems only Nikkor 2.8 pros

have fast autofocus speed. Tokina and the rest rate as slow. Is this

true? I don't want to end up with doggy auto focus.

[chris_ladoulis]

For AF speed, get the Nikkor 28-70/2.8AFS and the 70-200/2.8AFS-VR (or the discontinued 80-200/2.8AFS). You'll notice a very big difference in AFS vs. non-AFS, especially with the older/slower AF speed of the F4.

[todd peach seattle, washi]

The F4 benefits nicely from AFS lenses, even though the camera pre-dates the lens designs. It dramatically improves the AF performance of an F4 (I have not found a 'dramatic' AF improvement with AFS on an F100 or F5).

 

One might expect a similar 'boost' in AF speed from something like a Sigma HSM on an F4, but I haven't tried it.

[biotime_biotime]

Wellthe afs question I was reserving as another thread and I have been trying to get a definite answer about f4 afs compatability (I keed reading confliction info)BUT if I cannot afford afs how about the original question of older pro Nikon vs pro Tokina autofocus speed?

[biotime_biotime]

By the way what do you think of the test results at the photozone site?

http://www.photozone.de/bindex2.html

[hugh_t]

IMHO I think you would gain more AF with a newer body like the F100.

[todd peach seattle, washi]

I was tossing the idea of Sigma HSM into the ring as a possible inexpensive route to faster AF. I can't answer your Q about Nikon vs. Tokina AF speeds in the non-AFS regime.

 

There are a number of factors that go into 'speed of AF'. Assuming the same camera, non-motorized lenses, same scene, and same aperture, the AF speed usually comes down to 'driven mass' and the smoothness of the focus mechanism. My Nikon 85/1.8 AFD lens uses a 'rear focus' design and has very little driven mass. It's actually pretty responsive on an F4 and other cameras that are a little less than 'state of the art' for AF speed. In contrast, my Nikon 135/2.0 AF DC is pretty much a 'pig' for AF speed. An F4 or a D100 can't drive the 135/2.0 fast enough to track basketball. An F100 can.

 

I don't know anything at all about photozone. It has never crossed my 'radar' before (this surprises me a bit, because there's a lot of 'content' there). I note that in normal zooms, they don't have the Nikon 35-70 f/2.8 AFD listed. This is what you would compare to the Tokina for AF speed (non-AFS) in an f/2.8 'pro' normal zoom.

 

I can see why an LX man sought out the F4; they're both well thought-out 'system' cameras. The F4 has an almost cult-like following, but for some reason mine has not grabbed my imagination the way it has for others.