Focal Reducers – Lens Adapters That Change the Game

Lens Adapter

by Yaroslav AltuninJuly 24^th, 2021

The market for focal reducers has exploded in the last decade. These lens adapters have changed the way filmmakers look at cameras, lenses, and composition. But as with all new things, there has been equal amounts of love and hate, along with a healthy dose of misinformation. So what are focal reducers, what do they do, and why has Canon decided to make one? Let’s dig in and learn some stuff!

A focal reducer is the inverse of a teleconverter. While the latter increases the apparent focal length of a lens, a focal reducer does what it says on the tin: reduces the apparent focal length. It does this much like a magnifying glass, by taking the image circle produced by a lens (which is designed for a bigger sensor size), and shrinking it down so that the (smaller) sensor or film plane can capture more of the image produced.

It does what now?

All lenses produce a circular image. Hence, the term image circle. Usually, this image circle was only big enough to cover your frame. However, with the development of different films sizes, and now sensors, the mismatch between capture medium and image circle has never been as pronounced. Focal reducers and teleconverters alike, take advantage of this mismatch to sync up your image circle with the frame size of your capture medium.

And that is where some magic starts to happen. Focal reducers can not only make your images wider but also brighter and sharper. Why? ‘Cause science. Let’s take a look at a video from CVP to learn what is heck is going on under the hood.

Wow. That was a lot of math. But definitely worth it. As we see, by utilizing space that older lenses had reserved for flappy or spinning shutters, the elements inside focal reducers give new life to lenses once relegated to the shelf.

Canon grabs some market share pie

At the end of 2020 Canon released the Canon Mount Adapter EF-EOS R 0.71x. A 0.71x focal reducer that adapted EF mount lenses made for 36mmx24mm sensors (aka full-frame sensors), to Canon RF mount cameras that have smaller Super35 sensors. This is the first time a major manufacturer has joined the legion of companies currently making focal reducers. The first widespread use of focal reducers occurred when Metabones made their entrance into the market. They were the first to coin the term Speedbooster, a name they used for their products. Because of their prominence in the space, this term has become synonymous with focal reducers.

While Canon’s offering retails for $599.99, Metabones offers the same adapter and focal reduction combination for $479, as well as a myriad of other lens and mount combinations to choose from. While most focal or regular adapters don’t offer data passthrough, both Metabones and Canon maintain full communication between the camera and lens. The Canon adapter has also been specifically designed for the EOS C70 cinema camera and features an optional split locking collar to ensure a secure attachment.

Brands for all budgets

While Kinefinity also offers focal reducers made specifically for their camera, no other camera companies have ventured into this territory. When it comes to everyone else, that’s a whole different story. Here’s a list of companies that offer focal reducers at varying budgets and for unique camera sensor combinations.

• Metabones – The Grandfather of focal reducers with a wide selection of amateurs.
• Kipon – Great selection of medium format options. Check out our post on medium format cinematography.
• ABT Cine – DMC2 EF/PL Focal Reducer.
• LucAdapters – A non-adapter focal reducer for Blackmagic Design Cameras.
• Viltrox, Mitakon Zhongyi, Commlite, and Vello – Budget-friendly options.

All of these companies offer focal reducers at varying price points. Budget options can fall under $100, while some specialty products can cost more than $1000. We’re probably missing a few companies from the list so let us know in the comments if you use a brand that we didn’t mention.

Adaptable tools

Focal reducers were a solution that solved a technology transition problem. But in their utilization, they have become integral tools for filmmakers that have a single lens package and shoot on multiple cameras. They do have their limitations but create flexibility in an industry that continues to evolve in leaps.

As new cameras are released, almost every quarter it seems, there will always be gaps in the tools kits of filmmakers desperate to keep up. But if the influx of speed boosters, focal reducers, magic or turbo boosters is anything to go by, there will always a market to help build bridges over those gaps.

Do you have focal reducers in your tool kit? How have they helped (or hindered) your workflow? Which brands would you recommend?