Filters: When To Use A Camcorder Filter

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Jeff Sengstack, July 2009

Most cinematographers use filters. Most videographers do not. Why? Money, time and tradition. Besides, you can always fix it in post. Right? Not necessarily. There are some things filters can do that you really can NOT fix in post.

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Using filters can set you apart from the competition. And the super clarity of HD has image-sensitive personalities clamoring for filters to smooth out their wrinkles and rough edges. The question then is: will a competitive edge or HD cause you to bridge the filter divide? If so, what filters should you use? Video producer and junior college instructor Jeff Sengstack answers those questions in this tutorial.








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Lens filters are the mainstay of the film industry (Figure 1). When a director of photography rents a camera, a filter kit is invariably part of the package. And most cinematographers own a collection of filters they rely on to create a look that's uniquely theirs.

Filters traditionally go hand-in-hand with film, because film stock is rated for specific color temperatures. So, at the very least, if you shift locations and are shooting on the same reel of film, you need to use filters to compensate for different lighting.







Videographers, traditionally, have not relied on filters for a variety of reasons:

 * Color temperature is a non-issue for videographers. The camcorder's white balance control takes care of most lighting situations.

* Budgets for video shoots are typically much less than for film. So high-end filters that cost $100 to $500 each aren't on most videographers' radar

* Swapping filters during a fast-paced field production is a hassle, even if you use a filter holder (aka matte box).

* Video-editing software offers plenty of filter-like effects.

Overcoming Filter Phobia

Despite those issues, as a videographer you might want to rethink your filter phobia. Filters can improve your client working relationship. Jason Pedri, the owner of Roaring Mouse Productions in Cotati, California uses filters and a video monitor when shooting in the field with clients. Pedri says that a filter/monitor combination "empowers the client, gives them confidence to make suggestions about the shot and gives us more insight into what they had in mind for the shot appearance."

White Rabbit Productions in Salt Lake City attributes much of its success to the use of filters. Its mantra is, "We make people look good." To do that takes proper lighting and filters. White Rabbit's clients range from 60 Minutes, Dateline NBC and Access Hollywood to Disney, Dr. Phil and Oprah. "If we don't make clients look good, we lose those clients," says owner Sam Prigg. His teams use polarizing, ultraviolet, neutral-density, Pro-Mist, soft-FX and orange (85b) filters to create a warm film-like look, cut reflections, soften hard features and giving a light glow to faces.

Your Filter Kit

If you have not used filters in video or still photography, some of those filter names (and numbers) probably won't resonate with you. But all are worth considering if you want to venture into this higher plane of videography. Here's a rundown of some essential - or at least useful - filters. To demonstrate how these filters work, I've used images provided by The Tiffen Company.

Essential Filters

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* UV (Ultraviolet) - cuts through haze generated by ultraviolet light (not particulates like smog). Many videographers use a UV or a clear filter simply to protect their lenses and get some haze reduction as a side benefit (Figure 2).









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* Polarizer - increases color saturation and contrast (typically creating deep blue skies), while cutting reflections. There is no practical way digital F/X can replicate polarizing filters (Figure 3).

* Neutral Density (ND) - gray filters that absorb light evenly throughout the visible spectrum (they are rated by the amount of light they absorb). You use them when you want to open your f-stop to shrink the depth of field. This enables you to soften the background focus while keeping your subject in focus. Again...standard digital F/X cannot match the look of ND filters. 

Useful Filters

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* Color Conversion Filters - The most commonly used is #85 (amber - Figure 4) to reduce cool blue tones of outdoor scenes and video lights and warm up skin tones for a healthier look. #80 (blue) raises color temperature to make incandescent lighting appear to be daylight. 80 and 85 are examples of Wratten filter numbers, a system created by British inventor Frederick Wratten, who sold his company to Kodak, which now licenses Wratten-numbered filters to Tiffen.





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* Diffusion, Soft F/X and Pro-Mist (image-softening filters - Figure 5) - use combinations of etched-glass surfaces and a fine mesh to create softening, reduced contrast and a smooth look on textured surfaces. They reduce facial blemishes and wrinkles (to make people look good), while creating a natural film look. Depending on lighting, Pro-Mist goes a step further and adds a pearlescent glow to highlights

Those who work in high definition are turning to diffusion filters. "With HDTV, you see every flaw, every wrinkle," says Tiffen spokesperson, Jill Conrad. "By using Digital Diffusion FX filters, you are able soften these flaws while not having a filtered look."

Specialized Filters

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* Star Effect Filters (Figure 6) - use thin lines etched on the filter surface to create streaks of light emanating from light sources. The size and intensity of the star effect is dependent on the light source and the spacing of the lines. Narrower spacing produces brighter stars.



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* Infrared (Figure 7) - used traditionally with black-and-white infrared film, these filters can be used for color videography to penetrate aerial haze and display varying temperatures.



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* Graduated Filters (Figure 8) - split lengthwise into two halves - one part clear, the other with a filter -- with a smooth transition between the two elements. A typical use is to add neutral density to the upper half of a landscape (thereby darkening a washed-out sky), while keeping the ground properly exposed.

Chris Rowe, the owner of VideoBrite in Santa Rosa, California, uses an ND grad to subdue a portion of an image, thereby bringing attention to the area where he wants the viewer to look. "Filters are one way to set yourself apart from the average competition," Rowe says.






Shooting Day-for-Night

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Videographers frequently use graduated filters in day-for-night shots. Northern California filmmaker Stewart Kiehl, owner of Vineyard Video, shot a day-for-night scene for the film Halmani at high noon in the desert (Figure 9). To darken the scene, he stopped down three f-stops. To darken the sky, he used an ND grad along with a polarizing filter. He added a soft blue filter to further enhance the moonlit look.








Mounting Filters

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Kiehl and others who use filters frequently rely on a matte box mounted on the front of the camera lens or to rails attached to the base of the camera (Figure 10). Matte boxes allow shooters to easily add one or more filters, as well as to precisely adjust their positioning or rotation to ensure they are using filters like color-grads or polarizers to best effect. Matte boxes typically cost at least $500. If you work with multiple cameras, you can save some money by putting rails on all of them and swapping the matte box from camera to camera.

Matte box filters generally are rectangular and at least four inches on a side. If you want to avoid the extra cost of a matte box and its larger filters, you can buy round filters that screw onto the front of your camcorder lens that come in a variety of sizes. To check which size will work for your camera lens, look on the inside edge of the lens. There usually is the symbol "Ø" followed by the size in mm (e.g., 52mm). There's also a lesser price screw-on lens mount, similar to the one on this story's cover shot, which has four slots for filter lenses. It attaches to the same camera threads as a traditional screw-on filter.

Filters can give videographers a competitive edge. Yes, they are an extra expense and take time to set up, but the rewards can be happier clients, more intense images and that wonderful feeling that your work stands out from the crowd. 

Jeff Sengstack is an Adobe Certified Expert in Premiere Pro and Photoshop, author of three books on Adobe Premiere and a junior college computer science instructor. He recently completed a video tutorial for lynda.com on Premiere Elements 7, the consumer-level video editor from Adobe. 



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