ARRI Launches Dedicated EF Mount (LBUS) for the ALEXA Mini LF
Arri Ef Lbus Featured.jpg

The renowned camera manufacturer ARRI has just introduced the latest accessories for its large format film camera, namely the ALEXA Mini LF. This new EF mount (LBUS) not only supports covering large format sensors without vignetting, but also adds an LBUS interface.

The new bracket fits the ALEXA Mini LF, the original ALEXA Mini and the AMIRA. It does not fit any other ALEXA model, as these offer a different mechanical and electronic interface between the lens mount and the camera. In addition, LBUS only works on the Mini, not on the AMIRA.

On the left the new ARRI EF mount (LBUS), on the right the old one. Photo credit: ARRI


This new version of ARRI's own EF mount implementation offers a larger baffle so that an attached EF full-frame lens does not suffer from vignetting and has its own LBUS connection. The older EF mount remains available, however, as it still works perfectly for Super35 sensors such as the AMIRA.

EF cine lensPhoto credit: ARRI

You can of course also use the new version for Super35 sensors, but the connected LBUS connection only works with ALEXA Mini and Mini LF (read our coverage here).

Replacing the lens mounts is pretty easy and can be done without sending the camera in. Just make sure you are working in a clean environment and avoid dust getting into the camera.

Pancakes on EF mount (LBUS)A tiny pancake EF lens on the ALEXA Mini LF. Photo credit: ARRI

ARRI has hosted an extensive Tech Talk video session for the new EF mount (LBUS), which you can watch here (the mount "in action" from 6:18 am / detailed view and replacement of the mounts from 4 pm):

Over 140 million EF lenses

As of December 2018, Canon alone had shipped over 140 million EF lenses, almost two years ago, and Canon is by no means the only supplier of native EF glass. So the possibilities there are enormous as there is a large amount of EF glass out there. For this reason, ARRI decided to support these versatile lenses. The new EF mount (LBUS) now brings the world of full format EF to the popular ALEXA Mini LF.

EF Mount (LBUS)old EF bracket on the left, new EF bracket (LBUS) on the right. Photo credit: ARRI

EF glass can be divided into two main categories: classic still lenses and cine-style lenses. The former offers no iris control on the lens itself and no hard stops on the focus ring. These lenses will still work with the new EF mount (LBUS), but of course there will be some difficulties with the work (but you can control the iris with the camera, for example). Cine-style EF lenses, on the other hand, have all of the features you'd expect from real cine lenses and you can get them for far less money.

WCU-4Photo credit: ARRI

These full frame lenses can now be used in conjunction with the ALEXA Mini LF for a seamless recording experience. The LBUS interface offers the option of controlling the lens with motors and other accessories. However, the camera itself controls the mount so you can record lens data along with your footgae for seamless post production. You can also send lens data to be viewed on one of the camera's SDI ports.

Prices and availability

The new ARRI EF Bracket (LBUS) will be available this November and will retail for $ 1,755.

EF mount compatibility tableWhich bracket is compatible with which camera? Photo credit: ARRI


While the price may seem high, this little device has the potential to fuel your creativity when working with ARRI's ALEXA Mini LF film camera. Proper cine glass is heavy, very expensive and it is very difficult to find special lenses such as tilt / shift lenses, very long focal lengths, stabilized lenses (for which the LBUS connection provides power), etc. You can find all of this and more in the EF lens range.

Vinatge EF lensPhoto credit: ARRI

Pancake glasses, vintage glass that easily adapts to EF, as you call it. Of course, not every cine-style EF lens will match the optical performance of high-end cine glass, but in the end it's always the same: most of the time, it's better to get a (cheaper) set of a few lenses than just one have high end lens.

Link: ARRI website

What do you think? Do you work with ARRI ALEXA Mini LF cameras? Could this new EF mount add more possibilities to your workflow? Share your thoughts in the comments below!


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