Bro can u explain further on
The tracking vs afc. They are like similar when to use which.
In nex, there was touch screen, I mostly use tracking for video during dolly shot. For still never use before.
Now come to a7, not very clear. Esp the manual... Quite useless
Let's say u set ur focus point to centre (or spot). For explanation sake, there's a tree on the left, a man in the centre and a dog on the right in your frame. All different distance from u.
AF-C:
U half press on the man, then u move your camera so that the centre focus point go to the tree, your camera will focus on tree ( and any other things along the trail from man to the tree, if u move slowly). Your camera will auto adjust the focus based on the object where your centre point laid on.
Object tracking:
U focus on man, when u half press (and u set to activate tracking by half shutter press), your focus "green square" started to jiggle around and track the man. When u move your camera so that the centre focus point to the dog, the green square is still focus on the man.
Sony tracking is a bit more than this.
If u turn in face detection to track the face: happen that the mbs turn away while tracking, the camera will focus in the body, when the man turned back facing the camera, it will auto track the face again.
And A7&a7r has eye AF, to track eyes. That even cool!