cfcRebel wrote in post #13754610
Interesting finding, Jason. I noticed the contrary with my 7D.
When i used AF-point expansion + Main Focus Point Priority on a scenario where there was a perched bird, showing up about 10% of the frame. I have the "main" center AF point on him, thinking that should nail the focus. However, one of the AF-Expansion points picked up some leaves' movement a few inches in front of the bird (in other words, leaves were between me and the bird). Since i have "Main Focus Point Priority" set instead of "Continuous AF Track Priority" for my AI Servo, it ended up picking the leaves to focus on.
Similarly, I would imagine for the OP, to avoid having the AF incorrectly focus on the nose of the dog, shooting WITHOUT the Expansion points is probably going to yield more keeper.
I do find the AF Expansion comes in handy for bird-inflight where the subject stands out clearly against a pure background (blue sky).
Interesting finding, Jason. I noticed the contrary with my 7D.
When i used AF-point expansion + Main Focus Point Priority on a scenario where there was a perched bird, showing up about 10% of the frame. I have the "main" center AF point on him, thinking that should nail the focus. However, one of the AF-Expansion points picked up some leaves' movement a few inches in front of the bird (in other words, leaves were between me and the bird). Since i have "Main Focus Point Priority" set instead of "Continuous AF Track Priority" for my AI Servo, it ended up picking the leaves to focus on.
Similarly, I would imagine for the OP, to avoid having the AF incorrectly focus on the nose of the dog, shooting WITHOUT the Expansion points is probably going to yield more keeper.
I do find the AF Expansion comes in handy for bird-inflight where the subject stands out clearly against a pure background (blue sky).
Certainly there are times when that setting would yield less than optimal results. I personally wouldn't use either when shooting a bird with lots of obstructions around. I would use single point or spot and in that case continuous or main point is irrelevant (because of only using a single point). I have found that sometimes individuals get conflicting results with the same settings based. For that I don't have an explanation. I have found that to be the case with both my 7D (now sold) and my 1DIV.
