80d focus points

[chief54]

When shooting BIF sometimes bird is in focus other times not. When using single point or zone 9 focus points I will check where focus points locked in they show locked on bird/birds and shot is not in focus, or when shows focus points locked on background and not on bird/birds they are in focus as in image below any ideas why?

[ebiggs1]

When nothing is in sharp focus it is probably not the focus. Perhaps camera movement?

[jrhoffman75]

“focus points locked on background and not on bird/birds they are in focus as in image below any ideas why?”

I can’t judge focus on my iPad, but if you think birds are in focus but focus locked behind the birds then perhaps lens is front focusing?

Can you try with a different lens?

If nothing is in focus, then, as Ernie says, it could be camera shake. 

[Waddizzle]

I think you have just simply missed the subjects on this one particular shot.  Do not expect a 100% keeper rate, either.  We all miss the subject, and we might miss more often than we might want to admit, too.  Your [screen shows] only one AF point is active, with all of the rest being disabled, or inactive.

I think a single AF point is good for One Shot mode.  But, when using AI Servo you really need to take advantage of having multiple AF points active, so that the camera can collect more focusing data, most especially in Continuous Shooting modes.  You might try activating all of the AF points, just the 15 AF points in the center group, or the center point with either the 4 or 8 surrounding AF points. 

Also, there is a setting called "Image Priority."  I suggest that you set both 1st and 2nd Image Priority to full Focus Priority.  This setting causes AI Servo to behave a little like One Shot mode, causing the camera to not take a photo until there is a focus lock on something. 

The camera will tend to focus on the nearest subject, and more times than not your subject will be the nearest thing for the camera to focus on.  This is especially true when the background is outside of the DOF of your subjects.  I would also suggest opening up the aperture to f/8, which is the sweet spot for most lenses.  Your shutter speed is fast, and a faster speed to get the same exposure will not hurt anything.

I would also recommend using a monopod with a tilt head for this type of shooting.  Your Tamron will grow heavy, and wear on your arms, which will only increase camera shake on your part.  When using a camera support, you may also want to experiment with turning off the VC Image Stabilization.  At 600mm on an APS-C sensor, you can get away wtihout it.

[chief54]

thanks for suggestions I am using a tripod and same thing happens using the 15 points, which is what I use most of the time and I do have focus priority on both 1st and 2nd, this does not happen all the time but it is frustrating when you see focus lock on the bird and yet not in focus or not focus lock but bird in focus, just kinda weird. I have a keeper rate of around 35-40%, which I am ok with. but just can not figure out why some work. Here is one with nine point zone, one point locked and some editing.

[ebiggs1]

"...one point locked and some editing."

Some editing?  Go easy on the sliders, less is often more in photography.

[Waddizzle]

"thanks for suggestions I am using a tripod and same thing happens using the 15 points, which is what I use most of the time and I do have focus priority on both 1st and 2nd, this does not happen all the time... 

.... but it is frustrating when you see focus lock on the bird and yet not in focus or not focus lock but bird in focus, just kinda weird.

I have a keeper rate of around 35-40%, which I am ok with. but just can not figure out why some work. Here is one with nine point zone, one point locked and some editing."

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Yeah, a little too much editing on that image.  It almost looks like a complete background swap, too.

When you use multiple AF points, do you see the AF points blinking on and off [they will be grey, not red] as they track a subject?  The display can show you where it can lock focus, as it displays multiple AF points.  In AI Servo mode, it does not show you where it has locked focus, just which AF points have the potential to lock focus from one moment to the next.

If you miss your target, then it stops tracking your subject, but the AF system will keep hunting.  You can pause the AF, and re-acquire the subject.  This behavior is also programmable.  You can set how fast it switches from one AF point to the next when it is tracking.  You can set how fast it switches from one AF point to another when you lose tracking on a subject.

Also, make sure that you are NOT using Spot Focus when using just a single AF point for shots like your sample. 

You are kind of far away.  Only one AF point can cover your  subject.  Being closer would also help improve your keeper rate, because more AF points will be feeding data to the AI Servo focus tracking system.  Although 35-40% is really not all that bad for action shots of BIF.

[chief54]

here is same bird, using center 9 focus points with two locked on birds right wing and no editing, still a little fuzzy,not sure if i mentioned all images I use a Tamron 150-600 and it is on 600mm so i cropped this

[chief54]

here is one which is pretty much in focus using zone with center nine and 4 locked on but behind the bird, I am really confused how can it be in focus if none of active points is on bird

[Waddizzle]

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@chief54 wrote:

here is one which is pretty much in focus using zone with center nine and 4 locked on but behind the bird, I am really confused how can it be in focus if none of active points is on bird

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How?  Time.  A time delay between locking focus and the shutter firing has been introduced.

First, you are using One Shot AF, instead of AI Servo, for an action shot.  Using One Shot AF will almost always create a time delay between when the camera locked focus, and when you fired the shutter.

You are looking at the AF points that were capable of locking focus and locked focus on a subject.  You were half pressing the shutter when the four points locked.  They stay locked in until you release the shutter button, or ire the shutter.  You fired the shutter.  

Meanwhile, the goose continued soaring along, and out from under the locked AF points, before you fired the shutter.  The goose is in focus because it is still within the DOF of th locked focus points.  In other words, the distance between you and goose when you locked focus, and the distance between you and the goose when you fired the shutter a moment later, did not change significantly.