Testing out the AF today...

Phil Young

Phil Young

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Today I was taking some shots at sunset of seagulls in flight - started on 3D tracking but I just wasn't getting it so I switched to AF-C (auto).

Managed to get 58/101 shots in focus. (I was using a Tamron 70-200mm f2.8 VC)

I think that's pretty good but perhaps those with a bit more experience in relying on AF can confirm their thoughts? I think I might be under-valuing the D7000 af system slightly...?

Is 58% an average, good, very good etc hit rate for birds in flight with this kind of light???
 
Hard to say Phil. You have a good lens there and a capable camera, so if you can get the AF pinned on a contrasty target in good light, the equipment failure rate should be very low.

The tricky bit is getting the target nailed every time, and setting up the camera's AF in a way that gives you the best chance of doing that. Good BIF-ing is a real skill.
 
I can honestly say that after owning the D7000 for 2 years, I haven't used it's AF to it's potential but I'm not an avid birder so have little experienced idea about hit rates when it comes to good AF.

If it helps, the lighting was very flat.

One thing I am suprised at was how well the auto AF worked...didn't expect 1 in 2 shots to be on target.
 
FWIW, I find that using single point focus gives me more shots in focus. Other options for me ( I use a d700) are 9 points, 15 ? or is it 21 ? and then all 51 and finally 3D. With 3d, all that clever processing takes time, hence why I tend to go with single point. All the camera has to do is track focus. But saying that, I have had a lot of sucess with aircraft using the auto setting where it chooses any of the 51 points. My least sucess has been with 3D.
 
Thegreatroberto said:
FWIW, I find that using single point focus gives me more shots in focus. Other options for me ( I use a d700) are 9 points, 15 ? or is it 21 ? and then all 51 and finally 3D. With 3d, all that clever processing takes time, hence why I tend to go with single point. All the camera has to do is track focus. But saying that, I have had a lot of sucess with aircraft using the auto setting where it chooses any of the 51 points. My least sucess has been with 3D.
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Single focusing point? ...so you press focus a lot rather than hold the focus button?? ...is that making use of the D700 AF???
 
Or he's got good technique. If you can keep the rig aimed at the bird you're tracking, it should achieve and hold focus almost all the time, dropping it when the user misses his/her aim. Takes some practice but you should get a LOT more than 58% in focus.
 
Not brilliant IMO. I hasten to add that I don't do much bird photography but on the rare occasions I do, I tend to get 75%+ in focus (far fewer real keepers but not many due to missed focus.)
 
Nod said:
Not brilliant IMO. I hasten to add that I don't do much bird photography but on the rare occasions I do, I tend to get 75%+ in focus (far fewer real keepers but not many due to missed focus.)
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And is that what you think or you've actually gone through 100 shots to get that figure??? (Again, just trying to get an accurate response)
 
What I think. CBA to go trawling back through all my pics to see. As I said, it's not an area of photography I do a lot of.
 
Probably helps that I have all my bodies set to not fire unless AF is confirmed - the misses are almost always down to operator error - slipping off subject onto the background or getting something in front of it. Gulls are usually in relatively clear air and move fairly predictably, although looking up at them can be dodgy!
 
Nod said:
Probably helps that I have all my bodies set to not fire unless AF is confirmed - the misses are almost always down to operator error - slipping off subject onto the background or getting something in front of it. Gulls are usually in relatively clear air and move fairly predictably, although looking up at them can be dodgy!
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LOL!!!!! You bloody cheater!!!!!

You can't comment on hit rate if your af is set to focus rather than release!!!
 
No point in releasing if the results are cr@p.
 
A couple of button presses and you can create whatever OOF "masterpieces" you want to. Personally, I like in focus shots and would rather not waste effort and card space.
 
Nod said:
A couple of button presses and you can create whatever OOF "masterpieces" you want to. Personally, I like in focus shots and would rather not waste effort and card space.
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Inclined to agree I can't see the point in letting the shutter go if you've got af enabled and it hasn't confirmed focus as your just wasting card space.

Fine if your doing something else but bird for this scenario let the camera help you!
 
It would be interesting to see how many photographers have there cameras set to not allow release until AF confirmed.

I only have mine set to confirm AF on the first shot then 50/50 for the rest. I get better that the percentage that you've quoted Phil but it depends on how the bird is flying. I get better with a subject flying parallel than flying towards. Which I would expect.

I also think that "in focus" can be subjective. I'm sure that we've all had sequences of images that we have looked at and though I'm happy with that then to find one that is just absolutely razor sharp which suddenly makes the others look slightly off even though the majority of people would consider it sharp if viewed in isolation.

Best advice I could give would be to try various AF configurations. Centre, expanded, all points and practice using them in different situations until you get a feel for the best one to use. I only use all points if I'm photographing against a clean background where there is nothing to focus on but the subject.

You also may consider changing the response of the AF system so that it doesn't focus on another subject if you slip off the main one. You can slow down the refocus response to give you a chance to get back on target. It doesn't make it focus slower just not try and refocus too quickly.

Another technique that some use is bump focus. I've tried it and use it on occasion but I think that developing your own technique that works for you is down to experimenting and practice.

Merry Xmas.
 
Thanks replies folks and gaz, some good pointers there.

Actually when it comes to birds in flight I can really see how focus shutter release can be really helpful.

I'm going to try that next time I get out.
 
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