DENNY CLAIRMONT /
05.01.2003 12:00 PM
Fujinon's HDTV cine-style lenses

Video-camera manufacturers have been trying to gain a foothold in the film industry for a decade, if not more. But it was not until the introduction of a 24p HDTV camera that they started seeing some success. The ATSC developed the 24p format to produce a video picture that resembles a film picture in many respects, starting with the number of frames per second.



Fujinon’s HDTV Cine Style lenses, including the HAe5x6 SUPER Cine Style HDTV zoom lens shown here, provide the extra focus markings and gearing pitch that are common in the film industry.


Producers are making more movies and TV shows in HD, and equipment-rental companies are beginning to see an increase in demand for 24p equipment for production and testing. And there is growing interest among motion-picture producers about the purported benefits of digital video, which include lower production costs and lower film-to-process costs.

Until recently, a major hurdle in the acceptance of this format has been a dearth of HD video lenses that can mimic the functions, settings and quality of film lenses to which director-producers, cinematographers and camera assistants have grown accustomed. HD lens manufacturers had to address two issues in particular: “breathing” and “ramping.”

Lens breathing

Breathing is an industry term that refers to a lens’ tendency to make an image look bigger or smaller when its focal length is changed. In other words, when you change focus from something that is five feet away to something that is 20 feet away, the image size changes. This can have a disconcerting effect on the audience by making them aware of the camera’s presence.

Chances are that if you watch a documentary or news segment, you won’t be disturbed by the breathing of ENG-style lenses. When shooting documentaries, especially nature programs, you want to be as close as possible to that tiger and cub. And if the camera zooms in, the audience is normally not disturbed by the awareness that a camera is capturing the wildlife action. But imagine you’re doing a dramatic shot of a man sitting in a large plaza. Maybe he’s in Paris at a sidewalk café and he’s a spy, and he’s watching someone off in the distance. The camera first focuses on him, and then it changes focus to the person he is watching. Over the years, film-style lenses have evolved to the point where the breathing is so minimal that you don’t notice it. But, with ENG-style lenses, the effect is obvious and disruptive to the audience who, until then, felt like invisible observers.

Lens ramping

The other issue using video cameras outfitted with ENG-style lenses involves “exposure ramping” – opening the iris or increasing the gain on light sensitivity to compensate for darker environments. Zoom lenses are particularly sensitive to this feature. When you use a zoom lens, particularly one that has a wide angle, everything appears to be distant. At a certain focal length, a certain amount of light comes through that lens and ends up on the film or the image sensor. With a zoom lens, the “speed” of that lens – its ability to capture light – can change as you zoom to telephoto. ENG-type lenses have an automatic exposure control that causes either the iris to open wider or the gain circuit of the camera’s image sensors to increase their sensitivity.

But, when shooting drama, this is unacceptable. When you set up your scene, you don’t want the camera making decisions for you. As a director or cinematographer, you might want it dark and scary on that stalker hiding behind some trees. You might also want to see a little bit of his outline. And when you zoom in, you don’t want the shot to suddenly become bright and high key.

Markings, pitch

Film people also need a lens that has more markings for distances than ENG lenses. The man operating the video camera focuses by looking through the eyepiece at the image on the screen. That’s not the way to shoot dramatic films. The cameraman is busy composing the picture. Though he’s trying to watch the focus, that’s not his only job. The man standing alongside the camera, the camera assistant, maintains focus. He needs to judge or measure the distance between the camera and the subject and correctly focus the lens using the engraved numbers on the lens. Documentary and ENG guys don’t work that way. They just reach up and re-focus in the middle of a scene.

If you’re watching a program in which a tiger is giving birth to cubs, a momentary lapse of focus doesn’t bother you much. But, if you’re watching a dramatic show, a momentary lapse of focus is disruptive because it reminds you that the camera is present.

Finally, most video lenses also have a different gear pitch than film-style lenses. Film producers need lenses that have the gears in the same place and the same pitch as film-style focusing devices.

First to market

To serve the digital cinematography market, Fujinon offers film-style markings and gearing on its lenses, and addresses the breathing and ramping issues. The process started a few years ago when Fujinon visited Clairmont to find out what the rental company would like to see in digital lenses and photography. Fujinon has now come back with lenses that meet the rental company’s requirements for film-style lenses.

Recently, Clairmont purchased Fujinon HDTV Cine Style prime lenses and HDTV Cine Style zoom lenses, along with Sony HDEF900 HD cameras. The rental company bought three sets of eight HD Cine Style PRIME lenses and three HA10x5B-10 zoom lenses, which the film community refers to as the 5-50mm zoom lens.

These lenses provide the extra focus markings and gearing pitch that are common in the film industry. The focus ring turns much more than the 90 or 100 degrees you find on standard ENG-style lenses, which means that the increased number of focus markings are spread out in a more user-friendly way.

The gears on the lenses mate with the gears of the follow-focus controls because they have the same pitch (the spaces between the gear teeth have a 0.8 module pitch) to accept standard film lens accessories. Just as importantly, the lenses produce minimal breathing and ramping – two major issues film producers have had in the past with video lenses.

Unresolved issues

While Fujinon has stepped up to the plate in addressing the 24p lens questions, Clairmont still needs to resolve some issues to make 24p cameras right for people accustomed to working in film. Right now the rental company has Panasonic and Sony 24p HD cameras, and has borrowed Philips and Thomson equipment to examine and with which to experiment. All these cameras are built of thin die-cast magnesium, which is right for ENG and documentary people. They can throw these lightweight cameras on their shoulders and use them without getting tired. But the rental company feels that the cameras are not heavy-duty enough for its type of work. So the company is taking the whole front of the Sony camera and part of the top and bottom and remanufacturing it out of heavier-walled, strong high-grade aircraft aluminum. It has also changed the lens mount from aluminum to stainless steel. And, since the camera must be able to be easily mounted on a Steadi-Cam, the rental company has moved the camera’s controls from the front of the camera to other positions on the camera.

Other issues persist. Right now, not many post facilities are doing 24p post-production. The 24p editing systems are expensive and entail a steep learning curve. But Clairmont feels that it has to get involved and help this new medium mature. The availability of Fujinon Cine Style lenses should help make digital cinematography a true alternative to shooting in film.

Denny Clairmont is president of Clairmont Camera.




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