Picked up new camera and my first lens (switched systems entirely today), the zeiss 55. Now I've noticed the lens is still using firmware v.1 and I don't have my computer with me to try updating to v.2.

 

That said, I'm using P mode with afs and wide focus settings, and I'll focus on something (accurately) as usual right? Then after I release the half-pressed shutter button, focus should (on af single) remain on target, but it jitters and loses focus intermittently and kinda jumps around.

 

I wish I could update to firmware 2 on lens and see if it makes a difference. Any ideas?

Thanks for this. I had no idea firmware updates were available for the lenses. I should be getting my a7r2 soon as well, and I got the 55, and the 35 1.4, which both need updates.  

Well, as long as it focusses correctly when you half press it it shouldn't be too much of a worry when it loses focus when you let go of the button.

My theory would be that you have the "Pre-AF" function enabled which tries to pre-focus even before you press that shutter. when you move the camera then, it will try to find something to focus on.

Just look at your settings and see if you have Pre-AF enabled. If yes, disable it and see if it still happens...

Thanks for advice! I turned off "center lock on AF" and "pre AF" and it stopped. First A7 so still working out links. Lots of pixels so def seems moving subjects can blur at higher shutter speeds than I'm used to as well. That and playing around in menus def seems to tax battery. Love the color and contrast sooc though!

Also keep in mind that, after releasing the shutter button, if you half press it again the camera will obtain a new focus, which might not be the same as the previous one. The AEF/MF switch & button can be helpful to prevent that - might need a little configuration but IIRC the defaults were useful.

I prefer to set focus using one of the custom buttons, and disable the half shutter focus. Gives much more control on what your focusing on.

 

I used to use the button in the middle of the AF/AEL switch, but found it a bit uncomfortable. On the A7RII I just set the C2 button to AF and the C1 button to Magnification.

Duly noted. Thanks guys. I don't like that the strange jittery behavior exists at all, but maybe firmware update on lens or body will help. Anyhow focus is pretty accurate from my testing on day out yesterday!