Filmmakers of 2023 may not know what a depth of field (DOF) adapter is, but in the days before the DSRL revolution put full-frame video into everyone's hand, filmmakers had to rely on ground glass elements inside of an adapter that would allow camcorders to record the projection of any lens they chose.

Companies like Letus35 and P&S Technik crafted some amazing DOF adapters. The film 28 Days Laterby Danny Boyle used one such adapter to shoot on a Canon XL2, a camera that used Mini DV tapes.

But is the need for those tools long gone? Beastgrip doesn't seem to think so and has announced the third iteration of its smartphone DOF adapter, the MK3.

So, is this a tool that filmmakers need?

The Beastgrip DOF Adapter MK3

Made specifically for smartphones, the Beastgrip DOF Adapter MK3 uses the concepts from the old DOF adapters to mate full-frame lenses onto your smartphone.

Simply put, the adapter acts like a full-frame sensor that can be recorded by your smartphone, giving you all the features of full-frame glass without the camera.

The adapter attaches to your smartphone via the Beastgrip Pro rig or dedicated iPhone Beastcages. On the other end is an EF mount, which allows you to use a myriad of lenses since the popular Canon mount has produced countless first and third-party options.

From here, you can adapt anything else you want to Canon EF.

Your image circle is projected onto the internal focusing screen that your smartphone can then record. The new iteration includes a new optical design for better focus, more frame coverage, minimized distortion, and improved details.

Overall, it's a pretty cool piece of kit, but there are some things to consider before pulling out your wallet.

\u200bDOF Adapter MK3 for Smartphones

DOF Adapter MK3 for Smartphones

Credit: Beastgrip

Limitations of a DOF Adapter

Much like the original DOF adapters, the Beastgrip MK3 suffers from the same issues. Since you're projecting your lens onto a focusing screen, fast lenses are a must.

Beastgrip recommends lenses with an f/1.2 to f/2.8 for optimal results.

Furthermore, you're stuck in the manual world. For creatives that thrive off automated features like autofocus or internal lens stabilization, you're out of luck. Also, lenses without a manual iris ring just won't work with this setup.

Finally, because you're capturing the image from ground glass, there will always be some image degradation. You'll get some optical aberrations that will add halation around highlights, reduced contrast, and some color fringing. But this could play to your benefit, as it'll soften the overly sharp smartphone footage.

Beastgrip DOF Adapter MK3

Having full-frame cinema glass on your iPhone does have its benefits.

Credit: Beastgrip

Is This a Tool for You?

Here's where things get a bit tricky. Shooting on a smartphone is already a niche concept. Sure, we have feature films that have been captured with only an iPhone, and the new iPhone 15 Pro Max has features that belong on a full-blown production, but the issue still remains—you're shooting a phone.

The Beastgrip DOF Adapter MK3 takes that concept and gives it steroids. To get the whole kit to function, you'll have to build out the phone with a rig, and that feels like it defeats the purpose of shooting on your smartphone.

Having said that, there will be cases where a smartphone DOF adapter will be an asset. If you already have vintage EF glass and an iPhone, for just over $299 (retail price) you can be production-ready and start making some cool shorts or music videos. It could also be an interesting way to build out a director's viewfinder.

If this is something you think you'll benefit from, visit the Beastgrip Kickstarter to grab your unit.

As of this article, the crowdfunding campaign is already fully funded, which means there's a good chance this unit will go into production. However, there is always a risk with crowdfunding, so it's up to you if you want to pony up the cash.

Whether the DOF Adapter MK3 is right for you or not remains to be seen, but it's still great to see tools like this hit the market that give filmmakers even more creative opportunities.