I would like to describe how my two TAP adapters behave on my A7rII and A9.
But first recall from the
TECHART LM-EA7 Mount Adaptor Operrating instructions this page:
It shows the F-number settings one can choose to accomplish certain things.
I have in both cameras set F36 and shot an image.
Then either chosen F25 or F29 for my adapted lenses, shot a white image, and dialed the camera F-number to 2 and left it there.
As we know the actual F-number is mechanically set on the adapted lens.
I am using A mode, AF-C, and Flexible Spot S.
Cameras switched off, then attaching the TAP with lens.
Now, when I switch on the cameras, the TAP pushes out and then retracts, ready to be used with AF.
Now when switching a camera off, the TAP retracts all the way to the infinity focus position.
So far as I had expected.
Switching the camera back on, I hear a little noise, but the TAP doesn't push out the lens.
It simply stays at the retracted infinity position.
However, the TAP is nevertheless ready to be used with AF.
Simply point the lens at something and halfway press the shutter button. It autofocuses just fine.
Switch camera off and on, the same pattern happens again, etc.
Now switch camera off, detach the TAP just a bit so that there is no electrical contact, then attach again fully.
When switching the camera now on, the TAP pushes out and retracts, same behavior as when first attaching the TAP to the camera.
One more AF observation. The A9 with TAP successfully focuses in dim light when the A7rII is unable to.
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Now I would like to address an additional unrelated point when using lots of lenses with different focal lengths.
In this case it would be advantageous if one didn't have to use the Menu to switch IBIS on or off, or select the proper IBIS focal length.
In the following chart I show how to accomplish that for the A7rII and A9:
Of course Sony calls IBIS SteadyShot. One has to use 3 buttons to completely control SteadyShot without consulting the Menu.
The chart also shows my settings for the A7r and the a6300 that don't have IBIS=SteadyShot functionality.
While the A7r cannot be used with the TAP, the a6300 has support for the TAP.
The a6300 behaves similarly with TAP as the above described FF Sony cameras.
It also has the better AF in dim light, similar to the A9.
One more thing. I first have to attach the TAP to the a6300 before I attach the Meike battery grip.
Otherwise the Meike battery grip interferes with attaching the TAP. Such is life! Oh well.
BTW there is no such interference with the battery grip on the A7rII or A9.
AF/MF Ctrl Toggle is useful to switch back and forth between AF and MF.
Focus Magnifier for me is essential when using MF.
And finally the In-Camera Guide is handy when in the Menu.