Case focus on 5D MIII

[fbicking]

I have recently purchased a 5D MIII to replace my 7D. I was wondering if anyone had advise on what case to use to shoot my daughter who is a dancer. Most of her performances is as the principal subject so there are no other dancers around her. She also dances with a group but not that much. To me it seems that maybe I need to use one case when she is with a group and other when she is the principal.


Thanks 

[Harry Muff]

Confused… Case? Do you mean lens?




In which case I'm guessing the 100 f2 might do it for you. Cheap, fast and sharp.

[ishdakuteb]

i am not sure if i am correct, but case two i would pick since you want to shoot only your daughter from the crowd.  if there is no competition, then case one would also do the job in addition, pick cross focus points in the center for better result since it detects contrast better than any other focus points...

[jeffabbyben]

I believe this is what you are looking for.  Here is a focus guide for the 1dx that also applies to the 5d Mark iii.  It should be helpful.  Download the PDF file.

http://learn.usa.canon.com/resources/articles/2012/1dx_guidebook.shtml

[ChilledXpress]

I do believe you are speaking of the AF cases... I use Case 2 most of the time, tweaked a little for accel/decel.

 Case 1: Default tracking for general subjects.
 Case 2: Continues to track subject with intermittent obstacles blocking subject.
 Case 3: You can think of this as the opposite of Case 2. Instantly tracks new subjects entering the frame.
 Case 4: Good for subjects that are abruptly accelerating or decelerating.
 Case 5: For erratic subject movement.
 Case 6: Useful if you are shooting multiple skeet shooting themed weddings simultaneously.

[fbicking]

Thanks for the replies. So I am thinking that case 2 sounds the best this way if I am focused and a hand or arm move in front it will hold the focus. Didn't think of the cross type in the center for the focus. With the distance I am away I should be able to focus around the chest area and get a sharp face in focus. I always put my focus point on the face but in most situations I am far enough away that I am shooting with my 70-200 f/2.8L IS II lens. Even if I have to shoot at f/2.8 I should get enough DOF for the face to be sharp and I usually shoot at 320 shutter speed.

[drjlo]

Personally, I would shoot in one-shot AF mode instead of Ai Servo with 5D III.  With the AF speed of 70-200 II, one-shot mode is plenty fast for situations like this, and Ai Servo may end up giving you unpredictable results IME.