cdang wrote in post #18199592
I've been debating getting a used 7D2 instead of using a 1.4 for BIF..
At the moment I'm using case 3 with zone AF. Anyone using something different? Thanks for sharing your tips ߘ
Case 3 is intended refocus quickly on something else entering whatever AF points you are using. TS is set to +1 so it tends to drop focus on your primary subject that you have been tracking and refocus on something else. Lets say another bird flies in front Case 3 wants to drop the one you are tracking and refocus on the other. Good for shooting motorsports if you want to quickly shoot between one bike and another. Or quickly track two birds back and forth.
Case 2 is the opposite. TS is set to -1. It continues to track the bird even of another passes in front of it. Very handy when tracking and you go off the bird because it moves on you or you move by error.
Here is an example. I was tracking this gull. The previous shots had the AF point on it. During the burst sequence it swooped up. I got about 3 frames in as it moved up and it stayed in focus. This all happens in second and the difference between TS -1 and +1 makes a big difference. it is a screen shot it might not look good.
Here again a few weeks ago. The gull flew behind the branches and the system kept it in focus. It did not try to refocus on the branches. Case 3 would have tried to refocus on the branches.
I tend to use Case 2 and lower TS to -2 for precise tracking. For smaller erratic birds I'll use case 5 to 6 and one of the zone AF Modes. I also set TS to -2 for those Cases as well. A actually use small and 65 point zone quite often in Cases 5 and 6.
Case numbers have nothing to do with initial AF acquisition. The case numbers control AF tracking characteristics after initial focus has been achieved. We only have some limited control of initial AF acquisition via 1st and 2nd image priority on the purple menus, tab 2. I know Case 3 says "instantly focus on subject suddenly entering AF points" but that is after you have achieved initial focus lock on something else first.