Autofocus For Everyone!

Autofocus For Everyone

Fujinon just demonstrated their UA 107×8.4 AF Outside Broadcast Lens with Auto Focus at InterBEE 2019, the first box lens with stand-alone AF technology.

The Box Lens Goes Autofocus?

The past couple of years in camera technology have been kind of amazing if you look at the tools we’re now using objectively. One area that has grown in leaps and bounds is autofocus technology. At InterBee 2019 outside of Tokyo, Fujinon showed a fairly revolutionary lens.  They were demonstrating their UA 107×8.4 AF Outside Broadcast Lens with Auto Focus for the first time.

If you’re not familiar with what a box lens is, think about those pedestal-mounted large 2/3-inch broadcast cameras that are typically used to shoot live television. We’re used to seeing lenses in a cylindrical shape, but box lenses are so large and have such large glass elements, motors and electronics that it makes more sense to enclose all of the internals in a box-like rectangular housing, hence the name. This type of lens is large and heavy and would never be used handheld; they’re used in the realm of televising live sporting events and that sort of thing.

What was revolutionary about this new box lens that Fujinon demonstrated was that it’s the first lens of its kind that utilizes autofocus technology. The UA107x8.4 AF broadcast lens utilizes a brand-new phase-detection autofocus sensor; Fujinon says fast, sharp focus images with a response speed as quick as 0.5 seconds. Keep in mind the huge weight and diameter of the lens elements that the lens motors are moving to zoom and focus on a fast-moving subject.

The UA107x8.4 also features the company’s image stabilization mechanism and a 107x ultra-magnification zoom that covers focal lengths from 8.4mm to 900mm (1800mm with 2x)! Think about that for a second—an 8.4-900mm zoom lens with autofocus. The fact that this lens will retail for $212,000 is beside the point. The fact that it’s this type of lens with high-quality AF technology, which operates independent of the camera, is kind of amazing as there are no broadcast 2/3-inch removable lens cameras that have any sort of built-in AF. This is a lens company acknowledging that some of the highest-end televised events in the world can benefit from AF technology.

Trickle Up Technology?

Autofocus For Everyone
Fujinon also makes one of my favorite lenses, the XF16mm f/1.4 WR that utilizes, along with the XT-3 camera, similar technology for AF.

What’s also interesting to me is that this technology is the same AF technology that’s used in my mirrorless Fujifilm XT-3 camera and my favorite Fujinon XF16mm f/1.4 WR lens. Talk about two opposite ends of the production spectrum, right? It’s unusual but not unheard of for high tech features like AF to migrate from an $899 consumer lens and $1,400 mirrorless camera body to a massive 52 pound, 24-inch long box lens; it kind of makes you think that there’s something new afoot here with this “used to be consumer” AF feature, doesn’t it?  

My Pro Video/Digital Cinema AF Experience

Autofocus For Everyone
I’ve shot extensively with the Canon CN E 18-80mm t/4.4 IS compact servo lens with AF; it works well in documentary and event shooting.

Besides the Fujfilm XT-3, the other professional video camera that I own is the Canon EOS Cinema C200. In my time with the C200, I’ve had a chance to use many different lenses with it, from an inexpensive Canon 24mm f/2.8 pancake lens all the way up to some high-end cinema lenses that cost many times what the C200 itself costs. Here at HDVideoPro, I had a chance to use the Canon CN E 18-80 t/4.4 and CN E 70-200 t/4.4 servo zoom lenses with the C200 and the C300 MKII cameras. The one distinguishing feature that makes both of these lenses unique is that they’re high-quality servo zoom lenses that utilize Canon’s excellent dual pixel autofocus system. The CN E compact servos aren’t really cinema lenses, they have no hard stops and are geared more toward documentary and event shooters, but the fact that they are $4,600 high-quality lenses that utilize AF is notable. Not that long ago, fast-paced event and documentary shooting were both types of production that used to be the sole domain, on a pro level at least, of manual focus lenses. Now, we have choices.

The Newest AF Technology—Combined

Autofocus For Everyone
Sony’s new PMW-FX9 camera menu offers sophisticated AF controls that work well to acquire and track subjects, keeping them in razor-sharp focus in many different situations.

As I write this, I’m waiting for Sony to ship us out a review copy of its brand-new full-frame digital cinema camera, the PMW-FX9. The FX9, from preliminary reports from our colleagues in Europe, has some outstanding new AF technology built in that was adopted from the A7 mirrorless line up. Once again, AF technology is migrating upward. If you take a look at the menu of the FX9, you can see options for AF transition speed. AF responsiveness, Face detection AF and lots of other settings and parameters to fine-tune the FX-9 with.  

Autofocus For Everyone
The new Sony FX9 AF system works best with native AF Sony lenses like this 28-135mm f/4.0 G OSS servo zoom.

It used to be that most AF systems utilized either contrast detection, which didn’t always work very well on low contrast or low-lit subjects or phase detection, which reads the differing contrast ratios between adjacent pixels. With the new AF technology, Sony has figured out a way to layer a phase and a contrast-detection AF system over one sensor, which by all accounts gives you the best of both worlds.

Autofocus For Everyone
The Sony AF system utilizes both contrast and phase-detect AF technology sandwiched on a single sensor. The combined system works remarkably well in all kinds of conditions that usually cause AF to lose tracking.

The current Sony version offers a combined 824-point AF system that provides seamless AF that locks onto the subject earlier than other systems and tracks more faithfully through all kinds of lighting and contrast conditions.

The Next Frontier

While us medium to lower-end production users are enjoying and using different types of AF technology to help us shoot sharper and more in focus images, in the high end of narrative filmmaking and digital cinema, today, in 2019, ACs (assistant camera operators) mostly utilize wireless FIZ controls (Focus/Iris and Zoom) that, when paired with a small wireless video monitor, allows the AC to faithfully track focus. There’s a lot more to focusing the camera than just acquiring a subject and faithfully tracking it in narrative filmmaking. There’s a lot of emotion, drama and intent that the AC brings to how they focus the lens, how long the focus takes and when to shift focus from one character to another that just can’t be programmed to be taken care of by a camera’s electronics. At times, the challenge is just how to keep a subject in sharp focus with shallow DOF as the subject and camera move. That is an art and a skill, and many are skeptical about if any kind of autofocus will ever replace that.

Keep in mind, though, that this sort of creative, artistic focus pulling isn’t needed or used all of the time in narrative filmmaking. In some instances, creative focus pulling is a requirement, but in many other circumstances, there’s little need to be creative with focusing; the director mainly wants the main subject in the frame to stay in sharp focus, period. I’m personally convinced that autofocus technology is coming to high-end cinema optics, but it will probably be external rather than integrated into the lens body as it is in the lower end. This will allow current high-end optics to still be used, but in different ways: AF for some shots and sequences, manual focus with the AC for others. The future of the AC’s job description will undoubtedly shift in the coming years, from the fully manual focus pulling of today, often with digital distance finders/digital focusing scales, to the AC minding AF systems and then switching back to manual focus when needed.

There are focus pulls that I’ve seen that would be nearly impossible for a human AC to nail and had AF systems nail, but conversely, autofocus systems lack the human touch, visual signature and discernment. Yes, I’m of the opinion that what ACs do can be artistic, not just technical, and for autofocus to replace that is many years away with AI and learned behavior. In 2019, this aspect of filmmaking still required the human touch, but stay tuned, it’s evolving.