Sony A7RII and Techart AF adapter

Started 8 months ago | Discussions thread
roger2013 Regular Member • Posts: 221
Re: Sony A7RII and Techart AF adapter

I have used a Techart Pro (Leica M) on both an A7II and an A7RIII, and it works well, and I would expect the same to hold for an A7RII, though I have not tried that. I have used OM Zuikos (lots of them), Yashica 50 and 28, Leica R 35, 50 and 135. Cheap Leica M to whatever adapters work fine so long as you choose ones that are sufficiently narrow at the LM end to fit the TP. But I would echo two points made in other posts. Only use it with fairly light lenses because it is not clear that the construction is robust enough to support heavy lenses which could pull out the alignment. In my view, the Leica R 135 f2.8 is too heavy. There are threads on this problem. And it focuses by moving the entire lens, which means that with long focal lengths, you need to get the lens roughly in focus before using the autofocus.

Another issue, so I understand, it that if a lens focuses by moving the entire lens back and forth, then the TP should work as well as using the focusing ring on the lens. But if it focuses by moving some elements relative to others, the TP may give poor results because the lens needs to be exactly the right distance from the sensor/film plane.

The one wide-angle lens that does not work with the TP is a Voigtlander 10mm f5.6 (Leica M fitting), that I could not get to focus on infinity. My explanation is that such an extreme wide-angle is hypersensitive to small changes in distance from the sensor. But with a lens like this you hardly need autofocus because the depth of field is so great, and my solution was to buy a Fotodiox LM to E dumb adapter with a helicoid adjustment so I could adjust it to get infinity focus. I never had issues, aside from weight, with infinity focus on any other lens, from a 16mm fisheye to 200mm.

I never had problems with firmware updates or adjusting the settings, though I strongly recommend making sure you keep a record of what the different aperture settings on the camera do to the adapter. I have been out in the field and suddenly thought “What aperture do I need to get to make the TP park itself at infinity/closest focus/current distance?” The system of using aperture settings to change the adapter settings takes some getting used to, but it works and the company deserves credit for its ingenuity.

It can be fun to go out and use manual lenses though I admit that I haven’t used the TP for a while, lazily opting for the convenience of a 24-105 zoom.

Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow