Understanding Auto Focus -Birds

I tried a couple new things, bird in flight (a big slooow bird in flight, lol) and stepping outside my comfort zone of single point focus. I thought I had the focus thing all figured out, but now I am uncertain. I was in AF-S Auto area. I should have been in AF-C, right?

I think AF-C would have attempted to keep the points on the bird as I held the shutter. Instead, the points are where the heron was when I first pressed the shutter? These 2 shots were part of a 3 fps burst and the camera probably did not refocus. Am I analyzing this correctly?

And what specifically is the screen shot telling me with all the focus points shown? Is it confirming that the camera 'believes' all those points are on the same plane and are in focus? Or is it maybe trying to find a median focus point among all the points? I am very used to just using one focus point.

Thanks for any tips.

Yes, AF-C always for moving subjects. As far as i know, the red squares are showing which focal points were active and which ones were locked onto your target.

Remember, the squares aren't exactly accurate in your viewfinder. They actually cover an area greater than what you see when shooting. So looking at this, I assume that it caught on to that bird and was correct in assuming that was to be your subject. The picture is sharp and very well developed, I can only assume you AND your camera were doing a bang up job!

EDIT: Oh, also, af-a will default to af-c if it senses a moving subject, so that might have been what happened as well in this scenario.

Thanks for the replies. I was out looking for a turtle to pose for me and this heron suddenly appeared and I totally forgot all my book learning and I started fumbling. I need to set up one of my user settings for BIF. I'm anxious to get back out and try it on af-c to see how the focus points end up.

Euro, I was definitely on AF-S. Other shots in the series got blurrier as the bird flew off at an angle and the focus points stayed in that pattern sometimes way off the bird. I have been avoiding AF-A because its not clear to me when it will switch. For instance, if I was panning on a bird, would it still sense motion and switch to af-c or would it stay on af-s? I have to practice with it.

I think the bird moved only sideways during the first shot so it stayed in focus.

nickt said:

Thanks for the replies. I was out looking for a turtle to pose for me and this heron suddenly appeared and I totally forgot all my book learning and I started fumbling. I need to set up one of my user settings for BIF. I'm anxious to get back out and try it on af-c to see how the focus points end up.

Euro, I was definitely on AF-S. Other shots in the series got blurrier as the bird flew off at an angle and the focus points stayed in that pattern sometimes way off the bird. I have been avoiding AF-A because its not clear to me when it will switch. For instance, if I was panning on a bird, would it still sense motion and switch to af-c or would it stay on af-s? I have to practice with it.

I think the bird moved only sideways during the first shot so it stayed in focus.

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Have you had any opportunities to determine how AF-A reacts when panning? I'm researching AF-A dynamic vs AF-C setting options for my D7000.

Camera Fun said:

Have you had any opportunities to determine how AF-A reacts when panning? I'm researching AF-A dynamic vs AF-C setting options for my D7000.

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I have not. Time has been getting away from me and I haven't gotten out much. I might have to just practice on passing cars. Lately I have been leaving focus on af-c with single point and using the af lock when needed. It's more predictable for me. I can read all day and think I understand these focus modes, but I'm having trouble with practical applications.
I think we need to find out how AF-A senses motion. Does it sense changes in distance from the lens? If not then it probably stays on AF-S. If you are panning and the subject distance does not change, then it might not matter if you are in AF-S or -C. Hopefully I'll get it figured out.

If stated this in other post. Maybe this helps.

​I shoot a lot of sports and I would set my camera to shoot anything moving to these settings.
Servo mode AF-C.
39 pt dynamic area setting (I've tried the single, 9 and 21 pt. But the 39 gave me the sharpest pics.).
Also set your AE-L/AF-L button to AF-ON.
You set your AE-L/AF-L button this way to work with the AF-C.
When set up like this, you use your thumb to press and hold the AE-L/AF-L button and your index finger on the shutter(not pressed half down).
By pressing and holding the AE-L/AF-L button it will make the lens continually focus on your subject, all you have to do is push the shutter when
you want to take a picture. It's the same as holding the shutter half way down but sometimes its hard to do that for a long period of time.

nickt said:

Thanks for the replies. I was out looking for a turtle to pose for me

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I love the idea of using AF-C on a Turtle

I shoot with a D50 and the older but still reliable 80-400VR and always shoot with AF-C regardless of my subject.

06Honda said:

I shoot with a D50 and the older but still reliable 80-400VR and always shoot with AF-C regardless of my subject.

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AF-S = Auto Focus - Single (focus)

AF-C = Auto Focus - Continuous (focus)

AF-A = Auto Focus - Auto (focus)...kind of a blend between the two other ones.

Just in case ya didn't know.

Love your photos. I am new at D7000 and love to take bird photos, can you tell me what mode you were shooting in and what lens? Thanks. I also have mine on AF-C as I was told to do.

Debrus said:

Love your photos. I am new at D7000 and love to take bird photos, can you tell me what mode you were shooting in and what lens? Thanks. I also have mine on AF-C as I was told to do.

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Thanks. The lens is the.... I'll paste it in here..... Tamron SP 70-300mm f/4-5.6 Di VC USD.

I was in P mode although I often shoot this lens in shutter priority. Af-area auto mode, but unfortunately in af-s. I should have been in af-c since the bird got more and more out of focus as he flew away while I held the shutter down. I think you might want menu item A3 set to off or short along with af-c. A3 is the delay before the camera considers updating focus.

Thanks, I use Nikkor 70-300mm and 55-200mm most of time to shoot birds. I am still understanding all the rules of photography. I just want a good hobby but also good photos.

Debrus said:

Thanks, I use Nikkor 70-300mm and 55-200mm most of time to shoot birds. I am still understanding all the rules of photography. I just want a good hobby but also good photos.

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Me too. I have been shooting mostly snapshots for 30 years. I was always interested in the technical end of things, but I'm just now trying to see creatively and put some thought in my shots. Have fun!