Gadget Bag: Special-Effects Camera Filters

Mention the word “filter” to a young shooter, and he or she probably will think you’re talking about a Photoshop plug-in. But to those who cut their teeth on Kodachrome 25 and Panatomic-X, a filter is a thin glass disc that attaches to the front of a camera lens. To avoid confusion, we call them “camera filters.” Most absorb a specific range of the spectrum and thereby add an overall color to the image. But not all filters alter colors. Some, like the classic soft-focus filter, change the image sharpness and leave the colors alone.

Certain filters can be used in combination with others, and it’s popular to use those discussed in this article with solid-color filters to create a unique result. But these shouldn’t be stacked on top of skylight, UV or other so-called “protection” filters because the additional thickness can cause the corners of the image to vignette, especially when your zoom lens is in the wide-angle position.

Can a Photoshop expert reproduce the effects of these camera filters exactly? Some will argue this point, but the general consensus is a qualified “no.” These filters change the plane of focus before the image is captured. It’s possible to achieve very similar results using editing software, but they won’t be 100 percent the same. And that’s a big part of the fun.

B+W Cross Screen 8x

There are six popular types of special-effects filters, and all deserve a spot in your gadget bag. The star filter makes any point source of light appear to burst like fireworks. When used to photograph a birthday cake, for example, the candle flames gleam like stars. This filter is technically a diffraction grating, and the surface is etched with a dense pattern of intersecting parallel lines arranged to create small squares. Its unique physical appearance gives rise to its alternate name: cross-screen filter. Depending on the pattern, you can produce four-, eight- or 16-point stars.

Schneider HD Classic Soft

However, it relies on a contrasty point source of light, so it doesn’t work well in bright or evenly illuminated scenes. Soft-focus filters (or diffusion filters) are the portrait shooter’s best friend; they can help obscure small wrinkles and other imperfections without destroying the image’s overall sharpness. They’re constructed in many different ways, depending on the brand, and are available in different strengths.

You can create a moody ambience with fog filters. In design and construction, they’re similar to soft-focus filters, but generally cause a significant reduction in contrast and sometimes obliterate fine detail. Try one the next time you shoot a sunrise for an eerie, supernatural effect.

If you want to feel as if you’re inside the House of Mirrors, screw in a multi-image filter. The surface of this thick filter is a symmetrical set of facets that intersect at carefully arranged angles to produce multiple images of your subject. There’s some degradation of sharpness because of the optical aberrations that are introduced by the cascading images, but color and focus are mostly unaffected.

Cokin Double Exposure

The close-up and split-field close-up filters often are classified as lenses, but they belong in this collection of special-effects filters. They’re available in different strengths (generally calibrated from +1 to +3) and can be used in various combinations, to allow you to get closer to your subject. Although relatively inexpensive, they produce surprisingly good results. The split-field is half close-up, half empty, so you can capture two distinct planes of focus simultaneously—one near and one at infinity.

Neutral-density filters reduce light transmission evenly without adding color or making any other changes to the scene. They’re labeled based on the amount of light they absorb: a 0.3 ND absorbs one stop; a 0.9 ND absorbs 3 stops. Standard ND filters are useful but boring. On the other hand, grad ND filters are cool because you can hold back exposure in part of a scene—the sky, typically—without reducing the exposure overall.

B+W offers more than 1,000 filters in standard screw-in configurations and more than 1,600 in all. Sizes range from 19mm to 122mm—essentially, there’s nothing they can’t fit. Many fall into the special-effects category, including every flavor mentioned here, as well as many others. For example, in the 55mm size, B+W provides four-point, six-point and eight-point star-effect filters. B+W was founded in 1947 and became part of the Jos. Schneider Optical Works in 1985. The merger of these giants has produced interesting products, including the world’s first filters with a water- and dirt-repelling multilayer coating.

Tiffen Digital Diffusion FX-1

If you own several lenses that have different filter sizes, you’ll love the Cokin Creative Filter System. Instead of using duplicate filters, you can use the same filter on (nearly) all of your lenses. All you need is one Cokin filter holder and an assortment of inexpensive rings in the appropriate sizes. The filters are square and slide securely into the holder, which makes it easy to adjust both the vertical and horizontal position—a key benefit when using split-field, grad ND and multi-image filters. Cokin offers one of the largest assortments of creative special-effects filters, including interesting masks and double-exposure trick filters.

Formatt Filters are mainly marketed toward motion-picture, video and broadcast-television camera users, but that doesn’t deter enthusiastic still photographers. The Supermist clear filter is a highly prized softening tool for knocking the edge off excessive sharpness and reducing contrast by slightly lightening shadow areas without detracting from the overall image. Formatt traces its heritage back to Reginald Morris, grandfather to the company founder, who worked for many years as chief physicist at Eastman Kodak and helped develop what’s now known as the Kodak Wratten Standard.

Heliopan supplies 13 types of polarizers, grad wide-angle filters and a full range of special-effects filters. For occasional close-up photography, nothing is more convenient than close-up filters. They can’t replace a true macro lens, but high-quality results can be achieved if you use a high-quality filter like those made by Heliopan. Available in four strengths (NL 1.0 through NL 4.0), they can be used in combination (NL 2.0 + NL 3.0 = NL 5.0, for example) for greater flexibility. All Heliopan filters are made from glass supplied by Schott (wholly owned by Carl Zeiss) and set in black, anodized brass rings.

Hoya UV

Somewhere on one of your lenses or in a gadget bag pocket, you probably have at least one Hoya filter. One of the world’s largest manufacturers of optical glass, including glass used for camera lenses, eyeglasses and photographic filters, Hoya is best known for its lineup of extra-thin, Super Multi-Coated polarizers, UV and skylight filters. The company also manufactures an assortment of special-effects filters, including the one-of-a-kind Rainbow-Spot that uses 1,270 ultrafine parallel grooves per inch to collect and diffract each point source of light into a rainbow of color—even outdoors. The Rainbow-Spot is available in thread sizes 39mm through 95mm, and in Bay 60 for Hasselblad lenses.

Heliopan Close-Up

Schneider Optics is a household name to the pros, and its special-effects filters are well known to major motion-picture studios because of their extremely high quality, outstanding performance and consistency from filter to filter. This consistency allows cinematographers to swap filters between cameras without varying the results. Schneider’s painstaking attention to production quality is evidenced in its line of Classic Soft filters. Designed to blend away small wrinkles and blemishes without diminishing overall sharpness, Classic Soft filters contain an array of precisely manufactured microlenses that are carefully arranged in a widely spaced pattern and sandwiched between two thin sheets of plano-parallel optical glass. The small percentage of light that passes directly through a microlens is slightly refracted, while the light passing in between the lenses is unaffected.

The result is a pleasing soft-focus effect without any clue that a soft-focus filter was used. Tiffen filters have been around for more than 70 years and have been a staple of pro still photographers and movie studios for almost as long. In addition to producing nearly every conceivable type and style of special-effects filter, the company also has one of the most interactive websites where you can preview effects. Check out the before-and-after story of Glimmerglass, Pro-Mist, Digital Diffusion, Smoque and other filters at the Tiffen website.