Panavision Sees the Light
"In 1993, I was invited to talk at an imaging conference in Rochester, New York, where I showed a lot of the footage of what I was doing. By that time, all of the work I was doing on commercials and documentaries was shot with my 35mm single-swivel system, and the results I was getting were extra-ordinary. After the demonstration, I was approached by [ASC members] Victor Kemper and John Bailey, who were so impressed with my demonstration that they asked if they could borrow my tape and show it to Panavision. When I got back to Australia the next week, [Panavision president and CEO] John Farrand was on the telephone, and I started my association with the company."
Not long afterwards, Farrand and the firm's executive vice president of R&D/Optics, Iain Neil, met with Frazier to further discuss the design of a lens system based on the Australian's fully-functional 35mm prototype. "When we tested my prototype on a bench," Frazier recalls, "it actually did pretty well. And I'd put that system together purely by eyeball! I had none of the sophisticated test gear that tells you whether a particular element is performing or not. And although my 35mm prototype only had one swivel, I'd already designed a second swivel and thought about putting in an image rotator. But with every bit of glass you add, you introduce a new set of problems. I knew that if I could get those further design elements together, we'd really have something that could benefit everyone."
Neil offers, "For 35mm film work, particularly feature films, you need extremely high-quality imaging if you're going to be intercutting with footage shot with prime lenses such as Primos. The Frazier lens system is equivalent to having maybe two or three zoom lenses in series. If a typical zoom lens has 20 elements, then this system is like having 60 lens elements one after another. Of course, we don't actually have 60 elements in the Frazier lens, because we have components like mirrors and prisms, but if you add up what they mean optically, it's like having 60 elements.
"We basically took Jim's original design sketch and figured out the most efficient way of achieving all of the features, such as the dual swivel tip and image rotator. His original design sketch actually showed something that looked fairly similar to the final Frazier lens."
Depth of Field
When one first encounters the Frazier lens, the system's most striking feature is the extraordinary depth of field it can achieve. While this is by no means the system's only asset, it is an integral part of its design and — given Frazier's initial purpose — the device's raison d'être.
Although this unusual lens seemingly defies the laws of physics, it actually achieves its expanded depth through natural means. "This device does have a very large depth of field, but it is not infinite," notes Neil. "The depth that is created does not break the laws of physics; it occurs because of the design of the optical relay system that is used. If you were to take a 10mm fixed-focal-length lens and put it on a camera, you'd get a certain field of view and depth of field at, say a T8 aperture. If you were to put the equivalent lens on the Frazier — which in this case would be the 14mm, which delivers about a 9.9mm field of view — you would actually have a similar depth of field. Now you may say, 'Wait a minute! If that's so, why do people talk so much about the depth of field with this lens? Why wouldn't they just rent a 10mm instead?' The reason is that with a 10mm lens, the diameter of the front element is about six inches. If you were to take a bumblebee and put it on that lens's front glass, it would only fill about five percent of your frame. Because of the Frazier system's optical configuration, when you put the bumblebee on the front of the 14mm taking lens — which is about an inch and a half in diameter — the bee will fill about half of your frame. Yes, you'd have a large depth of field, but more importantly, you're able to get objects really close to the front of the taking lens to get into macro magnifications. So in a practical sense, the Frazier system's depth of field is more available and useful.
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© 1999 ASC