The Guangzhou, China-based company Techart has officially unveiled the Techart PRO AF adapter, world’s first autofocus adapter for manual focus lenses. The adapter, which was teased last month, actually lets you autofocus with lenses that don’t have that ability.
This first adapter is for mounting Leica M-mount lenses on Sony E-mount cameras. Using the electronic contacts and phase-detection focusing system of the Sony camera (e.g. the a7 II and a7R II), the adapter moves the lens closer and farther from the sensor plane by extending and retracting. By changing this distance by a maximum of 4.5mm, the adapter can automatically focus the lens.
The Techart PRO AF weighs just 133g (~4.7oz) but can be used for lenses as heavy as 700g (~1.54lb).
In addition to using Leica M lenses, photographers can also use adapters to connect lenses from other mounts (e.g. Leica R, CY, PK, MD) to also use the autofocus functionality. The lens supports both single and continuous autofocus modes, can be used to reduce the minimum focusing distance of lenses, and can be paired with a mobile app for saving lens data and receiving firmware upgrades.
Here’s a 3-minute video introducing the Techart PRO AF and explaining how it works:
This video shows how quickly the adapter autofocuses a Leica Noctilux 50mm f/1 lens on a Sony body:
The Techart PRO AF has a price tag of $349 and will begin shipping in March 2016. Pre-orders can be placed on the Techart website, and there’s free shipping (during the promo period) and a 1-year warranty.
Update on 2/12/16: Apparently Pentax sold a similar 1.7x teleconverter two decades ago that also provides AF for MF lenses.