In an earlier post I showed some pictures with the Voigtlander 10mm VM lens on the Techart Pro adapter. I have now worked out the problem with this combination. In autofocus mode it works fine, but in manual mode it fails to get infinity focus. If the adapter is parked fully extended, it is too thick for infinity focus; if it parks not extended at all, then it is too thin. I guess that with longer focal lengths, the difference between min focus and infinity is large enough to cover a slightly short adapter, but with the 10mm, the travel is so small, that this is not possible.
The problem is, if I buy a regular dumb adapter, are any of them precisely the right thickness to get infinity focus at infinity on the lens, or do they err on the "safe" side by making them slightly too thin?
But fortunately the Techart Pro works well enough with autofocus, and the depth of field is so large, that I may well find that I can easily manage without manual focus.