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Optical Filters
Courtesy of Tiffen.
They're still the best choice for creative photography in the digital age. Here are the ones you need most.
The great shift from film to digital capture over the last five years has transformed the entire picture-taking process in incredible ways. Images are now stored on hard drives, flash memory cards, and discs as electronic files that can be retouched or altered in Photoshop or with other image-manipulation programs. Prints, even those shot on film, are digitally produced at stores, kiosks, online printing services, and on home printers. The major camera companies and independent lens makers have even developed completely new optical lines for consumer digital SLRs (DSLRs) with smaller-than-35mm image sensors. One thing that hasn't changed is the usefulness of optical filters - those amazing light modifiers that mount over your lens. They still provide the most direct, controllable, and convenient way to achieve everything from special effects, to polarization, to soft focus, and they'll even protect your precious lenses from damage, dust, debris and fingerprints.
The ultimate in creative control
Perhaps the single greatest thing about optical filters is that they let you create precisely the images you want at the moment of exposure-the way the majority of the world's most memorable pictures have been made. That's because you can preview the effects you'll get by simply mounting the filter and looking at the image in your SLR's viewfinder, electronic viewfinder (EVF) or LCD screen of your digital camera. You can't do that using electronic plug-in filters, essentially mini-programs that let you add effects or manipulate an image, but only after it's taken and has been downloaded to a computer. Being able to control color balance and other visual effects with precision and repeatability as you shoot is not merely a convenience-it also means that you are in charge of the creative process as it unfolds; therefore you truly own the final images you compose.
Technical advantages of optical filters
Filtering the light before it before it passes through the through the lens and strikes the image sensor has a number of important technical advantages. Optical polarizers actually polarize the light, and can eliminate reflections on glass and water surfaces while revealing sub-surface details, such as the contents of a window display and dramatic images hidden beneath a watery surface. You can't do that with after-the-fact plug-in filters, which only mimic filter effects. When using graduated or neutral density filters, optical filters let you match the brightness range of the scene to the characteristics of the capture medium, and get professional looking results even under tricky lighting conditions. This is especially important with digital cameras, which typically don't have a great deal of overexposure latitude. Finally, optical filters can provide a vast number of special effects, from starbursts to prismatic patterns, to specific types of soft-focus that are difficult to duplicate in post-production,
Why quality filters matter
Obviously, anything placed in front of your lens can adversely affect picture sharpness and fidelity, and that is why it's essential to use precision glass filters of the highest quality. One outstanding example is award-winning Tiffen filters, manufactured in the U.S.A. to the most stringent professional standards, and prized by top Hollywood studios for their consistency and overall excellence. That's because Tiffen filters are the only ones manufactured using ColorCore technology, a closely guarded proprietary process in which the filter material is permanently laminated in between two optical glass elements that are ground flat to tolerances of a ten-thousandth of an inch, and then mounted in precision metal rings.
The ColorCore process allows Tiffen to control the color and density of its filters, and the characteristics of special effects, with much greater accuracy than dyed-in-the-mass filters, which often exhibit color and density variations. When Tiffen filters are ground and polished, the ColorCore is not affected, so color and density remain uniform. In fact, if you hold a group of Tiffen filters having the same specs against a white sheet of paper, they all look identical-because they are. Try this with other filter brands and you're likely to notice slight variations.
Quick guide to must-have optical filters
Now that you have a clear idea why professional quality optical filters are essential tools for all kinds of photography, film and digital, here's a quick rundown on some of the most useful filter types and tips on when to use them. When detailing various filter effects that follow, it is assumed that the filter being described is mounted on your camera lens. Note: Many filters other than protective, UV, and skylight filters affect the exposure by decreasing the amount of light reaching the image sensor or film, but this is automatically factored in by your camera's built-in, through-the-lens (TTL) metering system. When using a handheld exposure meter, make sure to include the filter's correction factor into your exposure calculations.
Polarizing filters: Tame reflections and zip up the colors
Polarizing filters should be at the top of every photographer's must-have list because they have so many practical uses and unique capabilities. A polarizer is a two-piece, variable-control filter that works by selectively transmitting or blocking list waves depending on their direction of vibration. By turning its front ring and observing the effect in your SLR's viewfinder (or on your camera's LCD) you can eliminate or minimize reflections on many surfaces, such as water or glass (but not metal or mirrors), allowing you to see any details (such as the driver behind the sun-drenched windshield) that were obscured by glare.
Polarizers also let you increase overall color saturation, and to increase the contrast of clouds to make them stand out against the sky, both especially useful abilities when shooting landscapes and outdoor scenes. Opt for a top quality circular polarizer, such as the Tiffen Circular Polarizer, that won't affect the accuracy of through-lens metering and auto-focus systems, rather than a linear polarizer, which is designed primarily for manual cameras. By the way, Tiffen also offers special Wide Angle Circular Polarizers that are optimized for wide-angle lenses.
Using a circular polarizer: Your thumb points the way!
Polarizers won't provide dramatic effects on cloudy days or in all areas of a sunlit scene. To find the area of sky most effectively polarized with a circular polarizer, point your index finger at the sun with your thumb extended at a right angle (90 degrees) to your index finger. Now rotate your thumb around the axis of your index finger. The arc-shaped path formed by your thumb as you rotate it from left to right will indicate the band of deepest blue from horizon to horizon.
Protective filters: Save that pricey glass, and get a bonus
A UV (ultraviolet) filter such as the Tiffen UV Protector is a popular way to protect expensive and delicate camera and camcorder lenses against physical damage from dust, rain, finger oils and perspiration (which can etch glass!) or sharp objects. As their name implies they do absorb ultraviolet radiation that may show up as a bluish cast in pictures taken at high altitudes or over water, but other than that they have little visible effect on your pictures and can be left on your camera permanently. Other choices for protective filters that can be left on the lens at all times are the pink-tinted Tiffen Sky 1-A filter that absorbs about 50% of UV radiation and adds a touch of warmth, and the stronger Tiffen Haze-1 filter that cuts haze more effectively and absorbs almost 3/4 of the UV. None of these filters has any significant effect on the exposure and all are available in Wide Angle versions.
Special FX filters: Hollywood in your camera bag?
The range of special effects possible with optical filters is truly staggering, and the ability to add a precise effect just before taking the picture by simply screwing a filter onto your lens is truly liberating. It is impossible to detail every type, much less every individual special-effects filter available in this space, but it is hoped a few examples from the extensive Tiffen range will whet your appetite.
Starbursts: Tiffen Star Effect filters create gorgeous star effects at any point light sources in the scene, including bright reflections. They're available in 4-point, 6-point, and 8-point versions. The adjustable type of starburst filter lets you turn the front ring to position the arms of the star where you want them. An excellent example of the latter is Tiffen's Hollywood/FX Vector filter that gives a natural looking 8-point asymmetrical star pattern.
Smoke & Fog: The Tiffen Smoque filter creates an effect quite similar to that of a mechanical smoke generator used by the big movie studios without the expense and hassle. Tiffen Fog Filters simulate the effect of a natural fog, creating a soft glow and flare, resulting in a warm, romantic ambience. They're available in a range of strengths. Lighter grades take the edge off contrast and sharpness, while heavier grades create fantastic dreamlike effects. The Tiffen Double Fog produces a more natural heavy fog effect that retains sharpness while substantially reducing contrast.
Diffusion: Among the best diffusion filters for creating romantic images are Tiffen Hollyood/FX Filter series. All are available in lighter densities that produce subtle effects with little change in contrast or highlight flare, to higher densities that minimize facial imperfections, yielding a soft, classic look to portraits. Three stellar examples: 1. The Tiffen Soft/FX, which incorporates a tiny pattern of lenslets designed to put fine image elements like wrinkles and skin blemishes out of focus while leaving larger details, such as eyes, sharp. 2. The Tiffen Warm Soft/FX filter combines a Soft/FX filter with Tiffen's exclusive 812 warming filter that gives skin warm, healthy glow, thus providing two of the best portrait effects at once. 3. The Tiffin Glimmerglass, a unique filter that incorporates a random overall pattern or bright metallic specks to subtly soften fine details in a distinctive manner and add a mild glow to highlights.
Graduated filters: Selective contrast control
Graduated optical filters are typically half clear and half colored, with the area in between providing a graduated density transition (feathered edge) so the effect blends smoothly into the scene in a natural looking way. A graduated neutral density filter such as the Tiffen Color-Grad ND (available in densities of 0.3, 0.6 and 0.9) is an excellent way to reduce the actual brightness ratio of an excessively contrasty scene-one where the image sensor or film can't capture both the brightest and darkest areas in a single exposure. By rotating the Color-Grad so its darkest part covers the brightest areas of the scene (usually the sky), and its clear area coincides with the shadows, you can get a good overall exposure that looks quite natural.
Colored graduated filters like the Tiffen Color-Grad Sunrise and Color-Grad Blue can transform an average sunrise or sunset into something spectacular or turn a dull washed-out sky a breathtaking blue-all without affecting actual colors of the rest of the scene.
Neutral density (ND) filters: Sometimes less really is more!
Why would you want less light to reach your image sensor or film? Even when shooting at ISO 100 (the lower limit with many digital cameras) the ambient light level may simply be too high to let you take pictures at a wide aperture (even at the fastest shutter speed) to give you the shallow depth of field you need in order to, for example, de-emphasize a distracting background, Also, you might want to shoot at a slow shutter speed to emphasize the effect of motion, as when photographing a waterfall. An ND filter such as the Tiffen Neutral Density filter (available in densities o 0.3, 0.6, and 0.9) will let you do either without affecting color balance or color accuracy.
Specialized filters: Effects you probably never thought of
Can you imagine a filter that makes reds, rust browns, and oranges really pop while having hardly any effect on other colors? Tiffen did. They call it an Enhancing filter (it's available in a Wide Angle version) and its perfect for fall foliage, earth-tone rock formations and faded barns. For ultra-dramatic outdoor effects try it along with a Tiffen Circular Polarizer. Or how about a filter that lets you "see" more, capturing detail lost in shadows by lowering contrast evenly throughout the image, but with no flare or halation! It sounds almost impossible but Tiffen's Ultra Contrast Filter does all these things so effectively it received a Technical Achievement Award from the Academy of Motion Picture Arts & Sciences.
We hope that we've given you some cogent ideas on why optical filters are essential tools in this digital age and provided some useful suggestions on how you can use them to enhance your creative photography. Just bear in mind that filters are not only practical, useful and easy to use, they're also a heck of a lot of fun. And when it comes to the varieties that are available from Tiffen (pardon the pun) we've only begun to scratch the surface.
Vist Tiffen.com
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