I received my adapter last Saturday, and have shot several hundred photos since then.
I've been using "Flexible Spot: S" successfully, the only photos that have not been in focus were the result of user error (i.e., firing without first pressing back-button AF.)
A few notes:
Mine apparently came with firmware version 1. However when I looked at the version number, it originally said:
Lens
Ver. 02
So I originally thought it shipped with firmware version 2.
After updating to version 2, the motor is less 'chirpy' and focus seems a bit slower, but that may just be an initial impression as I just updated it a few minutes ago and have only done a few tests around the house.
Now, when I go to the Version screen on the camera, it shows:
Lens
Ver. 01
As far as where to put the focus ring on the lens, I leave it on infinity, unless the subject is relatively close.
For example, with the 50/1.7 C/Y, the minimum focus distance is 0.6m. That's a little long for my preference with SLR lenses (the 50/1.4 C/Y has an MFD of 0.45m for comparison) so the Techart adapter is very useful, as it's in effect a built-in, on-demand, variable extension tube.
So, if I'm shooting something that is in the range of about 1m to infinity, I leave the lens on infinity.
If the subject is fairly close, however, say, in the range of 1m or less, I'll turn the focus ring on the lens until things look reasonably sharp in the viewfinder, then hit the back-button AF to lock focus. After a bit of practice this becomes second nature, and the motor in the Techart only has to move very slightly to lock focus.
The above would be the recommended usage for lenses with floating elements; coarse focus manually, and then press AF button to lock.
If the lens is
NOT at infinity, and you try to AF on something farther away, the Techart might not be able to reach focus. At first I was wondering what was up, but it was just user error.
In this situation the motor moves a bit, but never 'beeps' with focus confirmation and the green square doesn't light up. Set the focus ring to infinity and then press the AF button again.
At first I wasn't able to use focus magnification, but finally figured out that AF/MF Ctrl has to be toggled first.
So in AF mode, you won't see focus peaking, and you won't be able to magnify. This error will appear:
“This operation or setting
is not available as follows
Focus Mode
Single-shot AF”
Toggle to MF and focus peaking will appear, and magnification is then possible.
My camera has AF/MF Ctrl Toggle set to the Center Button, Focus Magnifier set to C2, and Steady Shot Focal Length set to C4 (trash can.) This arrangement was suggested by Chad (@Show Performance.)
Hope this helps!