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?

[Waddizzle]

You seem to be doing the exact opposite of how i use my cameras.  Typically, i use only the center AF point when I am using One Shot focusing mode with Single Shot drive mode.

Typically, I will enable multiple AF assist points when I am using AI Servo.  The above was shot with all AF points active, using AI Servo focusing mode, and Continuous Shooting drive mode.

[chief54]

I understand know, I usually use my 80d and have it on AL Servo, I was experimenting with 6d and forgot to change. Also I use back button focus on both cameras.

[ebiggs1]

"I understand know, I usually use my 80d and have it on AL Servo, ..."

You have to walk before you can run.  I would use One shot and just the center focus point.  Turn all the others off. The 150-600mm super zoom is a lens that needs practice. You are dealing with some serious focal length.  You have several problems cropping up. When you magnify a subject by as much as 600mm does, you also magnify all the problems by the same amount.

Let's go back to basics. Do the One shot and one AF point.  SHoot stationary or slow moving birds for a while.  Until they come in sharp focus to your liking. Shoot Raw format and back off on the editing sliders. Always do a lens correction as your first edit. I guarantee you will get to the results you are seeking with this method.

[chief54]

sound advice, though still not sure why this photo is in focus when none of focus points are locked on birds, I am missing something in explanations and advice. This was on a tripod with manfrooto gimbal head, raw, no editing, with right settings although not single point but 9 point, would it have worked with just single point locking in same palce,

[chief54]

same sequence two frames later, so within a second or so, why is this one not in focus, the frame right before was in focus with out focus points on bird, what am I not grasping

[Waddizzle]

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@chief54 wrote:

same sequence two frames later, so within a second or so, why is this one not in focus, the frame right before was in focus with out focus points on bird, what am I not grasping

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You are simply not locked onto the subject.  The AF points seem to have lost the BIF, and locked onto the background.   

Those shots could have been tack sharp with all AF points active in AI Servo mode.  Then again, the shots could have have been tack sharp with One Shot using just the center point, too.  

You mentioned using BBF.  I only use BBF with One Shot focus, Single Shot drive, and Center Point AF.  I think of it as “bird on a tree branch” mode, and save it as a custom shooting mode, C1.  I use BBF because I do not want the camera to refocus when I press the shutter.

I program C2 to be nearly the exact opposite.  I use the BBF point as “AF-OFF”, Ai Servo focus, Continuous Shooting drive, and all AF points active.  I think of this as “BIF” mode, because 9 times out o 10, the camera will focus on the nearest subject, and that subject will be your BIF.

Starting of with a tripod, and shooting stationary critters is good advice.  You do not have to limit yourself to birds.  Squirrels make good subjects.  There is a park near my house, and if I sit on a bench for 15 minutes, all of the critters come out of hiding: rabbits, squirrels, chipmunks, etc.  I learned hoe the camera behaved doing this.

Once I thought I knew how the camera/lens combo behaved, I tried AI Servo with just one AF point, one zone of AF points, and finally all AF points.  Most of my BIF shots are handheld, and frequently the monopod may be hanging from the bottom of the lens.  Sometimes you do not have time to disconnect the monopod.

[chief54]

Waddizzle, I appreciate advice, but once again 1st image of geese is not locked on bird, yet it is in focus, why? I understand the image with 4 focus points is not locked on bird but on the background so bird is not in focus, I get that but previous image has focus point not locked on geese but they are in focus, niether image has focus points locked on geese yet one is in focus the other is not. That is why I am not getting this. why one is in focus and other is not

[Waddizzle]

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@chief54 wrote:

Waddizzle, I appreciate advice, but once again 1st image of geese is not locked on bird, yet it is in focus, why? I understand the image with 4 focus points is not locked on bird but on the background so bird is not in focus, I get that but previous image has focus point not locked on geese but they are in focus, niether image has focus points locked on geese yet one is in focus the other is not. That is why I am not getting this. why one is in focus and other is not

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First, it is not possible for us to judge focus from a screen shot.  If you say it is in focus, then I will take your word for it.  The Birds are in focus because they could be within the DOF of the AF points that locked focus.

Second, you there is a time delay between the AF points lock focus, and when the shutter fired.  This delay is longer when you are using One Shot focusing.  Your subjects are constantly moving, your camera could be moving, so the captured image can be misleading.  What is important is that it locked focus on something, compared to not locking focus on something.

[ebiggs1]

"...same sequence two frames later ..."

Same thing.  Time lag and incorrect panning.  The AF locked and the shutter fired but you were off target.  The AF will not refocus until you release the shutter in One shot.  In Ai-servo it will continually refocus but not necessarily on what you want.

Let's go back to basics and get your confidence back up with a few good shots.  Slowly graduate to the move difficult faster birds.

[ebiggs1]

"...why this photo is in focus when none of focus points are locked on birds,..."

Two things time lag and incorrect panning.