Nikon D300 rapid focussing!

[Dave Pickett]

Picked up and played with a D300 in Park cameras tonight, the speed of focussing is balistic compared to my D90 which I thought was quick enough!

D300 had the 60mm Micro Nikkor, D90 the 18 - 105 std lens. I defocussed completly then focussed and the D300 was much quicker.

Question: since both lenses were AFS and had the built in motor, is it the camera or the lens affecting the focus speed?

 

[JDholic]

It's the d300, it shares the same af system as it's big brothers d3 etc.

The d90 will have to do for me though!!

 

[fracster]

Both mate,for example my 80-400 focuses much faster on the D300 than on my D200.It is a slowish lens. The 17-55 and 80-200,for example, are both very fast lenses,but they both seem to focus faster on the 300 than the 200.

 

[towershot]

I agree with fracster, it's a bit of both.

 

[StewartR]

If both lenses were AF-S then the body will not be making much difference. The AF system in the D300 may be able to make decisions fractionally quicker (and perhaps more so in poor light), but if you're talking about refocussing from one end of the range to the other then it's the motor within the lens which is the main factor.

With AF lenses like fracster's 80-400VR it's a different story though. Higher-spec camera bodies will have more powerful and more highly-torqued focus motors in them, so the lens will re-focus faster.

 

[alex_m90]

If both lenses were AF-S then the body will not be making much difference. The AF system in the D300 may be able to make decisions fractionally quicker (and perhaps more so in poor light), but if you're talking about refocussing from one end of the range to the other then it's the motor within the lens which is the main factor.

With AF lenses like fracster's 80-400VR it's a different story though. Higher-spec camera bodies will have more powerful and more highly-torqued focus motors in them, so the lens will re-focus faster.

Does this mean that a lens that has a built in motor that is slow at focussing, e.g. Tamron 70-200 2/2.8 will be faster at focusing on the D300 than on a D40X then?
Also does the body have any influence on how much the lens will hunt etc?

 

[-Rob-]

Both mate,for example my 80-400 focuses much faster on the D300 than on my D200.It is a slowish lens.

I've been out today with my D300 and a friends 80-400mm and I thought the speed of focusing was awful. OK so it's got some big glass in there to move about but I was expecting it to be better. I was attampting to photograph owls in flight which I know wouldn't be easy but I didn't get a single flight shot any where near in focus. Next time I'm going back with a 70-200mm 2.8 VR to see how I get on.

 

[StewartR]

If both lenses were AF-S then the body will not be making much difference. The AF system in the D300 may be able to make decisions fractionally quicker (and perhaps more so in poor light), but if you're talking about refocussing from one end of the range to the other then it's the motor within the lens which is the main factor.

With AF lenses like fracster's 80-400VR it's a different story though. Higher-spec camera bodies will have more powerful and more highly-torqued focus motors in them, so the lens will re-focus faster.

Does this mean that a lens that has a built in motor that is slow at focussing, e.g. Tamron 70-200 2/2.8 will be faster at focusing on the D300 than on a D40X then?
Also does the body have any influence on how much the lens will hunt etc?

What I'm saying is exactly the opposite. If the focussing motor is in the lens, then (in normal conditions etc.) I would expect that the camera body will only have a small effect on the speed of focus. If the Tamron 70-200 is slow to focus on a D40X then I'd expect it to be slow to focus on a D300.

I should stress that I have no direct evidence of this. My weapon of choice is a Canon, and Canon have been putting the focussing motors exclusively in their lenses since 1987. But my hypothesis is testable and falsifiable. If I'm wrong, someone with more Nikon experience will doubtless come along and say so.

 

[puddleduck]

Does this mean that a lens that has a built in motor that is slow at focussing, e.g. Tamron 70-200 2/2.8 will be faster at focusing on the D300 than on a D40X then?
Also does the body have any influence on how much the lens will hunt etc?

No, for a lens with a built-in motor the camera has no influence on internal lens speed movements.

The body is everything to do with hunting - a lens cannot "hunt" on its own if you think about it. Auto focus sensor usage (ie cross hair, outer AF point), plays it part.

I could talk about uncorrected spherical aberation but I don't really want to go there - suffice to say older AF modules (CAM900) did much better with this than the newer ones.

 

[fracster]

I've been out today with my D300 and a friends 80-400mm and I thought the speed of focusing was awful. OK so it's got some big glass in there to move about but I was expecting it to be better. I was attampting to photograph owls in flight which I know wouldn't be easy but I didn't get a single flight shot any where near in focus. Next time I'm going back with a 70-200mm 2.8 VR to see how I get on.

It ain`t the fastest in the world,that is for sure.But I have got some good action shots with the setup,dragonflies in flight for example.Perhaps the ,I assume,poor light was a major factor........:shrug:

But yes,you are correct,the 80-400 is not AFS speed,but if you adjust your technique to compensate,then it ain`t to bad.

 

[singlespeed]

The body is everything to do with hunting - a lens cannot "hunt" on its own if you think about it. Auto focus sensor usage (ie cross hair, outer AF point), plays it part.

I found the Tamron 70-200 f2.8 to hunt quite regularly on my D60 unless it was being focused on an area of high contrast. However with it on the D300, the hunting still happens ocasionaly but is noticably better and tracking is normaly good I don't think the speed of focussing is any faster, just more reliable.