Today many photographers use digital filter software systems.
Systems such as Tiffen Dfx v3 or Photoshop Lightroom 5 are widely used instead of traditional optical glass filters to enhance their images and achieve a staggering variety of visual effects in post-production. While these filter emulation systems are impressive in terms of their flexibility, glass filters that screw into your camera’s lens belong in every serious shooter’s camera bag because they let you do a number of important things that can’t be accomplished in any other way. And, like interchangeable lenses, they let you achieve a wide variety of effects simply, predictably, easily and at the moment of exposure when your creative juices are flowing.
In short, optical filters operate on the exact same principle that defines DSLRs and Compact System Cameras—what you see is what you get! When you mount a filter over the lens, you can observe its effect directly in real time before you press the shutter release. And when you capture the precise effect you want, it’s an integral part of the original image file, not a layer added in Photoshop or plug-in filter effect applied in post-production. Certainly many outstanding images have been created or successfully enhanced on the computer. However, there’s also something very special about creating the final image in camera the moment of exposure, a technique that has resulted in some of the world’s greatest and most memorable images. Optical filters let you do just that!
Optical filters for digital imaging
Using optical filters on your DSLR or Compact System Camera
The CMOS or CCD image sensor in your camera responds to light—and to filters—in much the same way as film. Therefore any filters you used back in the day with color film will provide virtually the same effects in digital capture. These include polarizing filters, soft-focus and special effects filters, UV protective filters, color-enhancing filters, graduated filters, and warming and cooling filters that provide a redder (warmer) or cooler (bluer) color rendition. Color conversion and color compensating filters designed for shooting daylight-balanced slide film under indoor household illumination (e.g. the 80 series) or vice versa (e.g. the 85 series), are not all that useful with digital capture. That’s because all DSLRs provide auto white balance (AWB) and offer specific manual settings for Daylight, Tungsten, Overcast, and other general lighting conditions. However light balancing filters (e.g. the warming 81 series) or cooling filters (e. g. the 82 series) can be quite useful in providing predictable effects that you can preview in your DSLR’s finder. Whenever using any color filter on a DSLR NEVER use the Auto White Balance (AWB) setting or the color effect of the filter will automatically be canceled out! ALWAYS set the White Balance control to a MANUAL setting that corresponds to the prevailing lighting condition (e.g. Daylight) BEFORE mounting the filter. That way the recorded image will look very close to what you saw in the viewfinder.
Essential filters for DSLR photography
If there is any single optical filter that belongs in the every digital shooter’s camera bag, it’s the polarizer. Examples: the Tiffen HT Circular Polarizer (which uses proprietary titanium multi-coating for enhanced light transmission, easy cleaning, and durability) and the B&W Digital Pro Circular Polarizer. A circular polarizer is preferable to a linear polarizer because it won’t adversely affect the metering or auto-focus performance of DSLR cameras that incorporate beam-splitters in the optical path—that is, virt5ually every DSLR in current production. 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 DSLR’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 contents of a store window display) that were obscured by glare. NOTE: No plug-in software filter can provide true polarization that will eliminate glare and reveal obscured details. Polarizers also let you increase overall color saturation for a more vibrant color palette, and increase the contrast of clouds to make them stand out against a deep blue sky, both extremely useful abilities when shooting landscapes and outdoor scenes.
Protective UV filters: First line of defense for your prized lenses
It makes a lot of sense to protect a camera lens that may cost $500-2000 and up with a simple device that’s readily obtainable for less than 50 bucks! That’s probably why so many savvy DSLR shooters mount a clear glass or UV filter such as the Hoya EVO UV filter or the Tiffen UV Protector to protect their pricey glass against dust, moisture, fingerprints (which can etch glass!) and other physical damage. They can be kept on your camera at all times because they have virtually no effect in ordinary picture taking, but, as the UV designation implies, they will absorb ultraviolet radiation that’s invisible to your eyes. UV may shows up as a slight bluish tinge in images taken at high altitudes or over water with film or digital cameras. None of these filters has any significant effect on the exposure and all are available in wide-angle versions.
Graduated ND filters: Selective contrast control with a twist
Graduated optical filters are typically half clear and half tinted, with the area in between providing a graduated density transition (feathered edge) so the effect blends smoothly and the captured scene looks natural. Using a graduated neutral density ND filter such as the Tiffen Color-Grad ND (available in densities of 0.3, 0.6 and 0.9) or the Heliopan 2X Graduated ND filter is an excellent way to reduce the actual brightness ratio of a scene with excessive contrast or brightness range—one where the image sensor or film can’t capture both the brightest and darkest areas in a single exposure. By rotating the graduated ND filter to position its darkest part covers the brightest areas of the scene (usually the sky), and its clear area to coincide with the shadow areas (typically the foreground), you can get a good overall exposure that looks quite natural. Colored graduated filters like the Tiffen Color-Grad Sunrise that can transform the average sunrise or sunset into something spectacular without significantly affecting other colors in the scene.
Neutral density (ND) filters: Sometimes less really is more!
Why would you want less light to reach your image sensor? 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 and make the subject “pop”. Also, you might want to shoot at a slow shutter speed to emphasize the feeling of motion, as when photographing a waterfall. An ND filter such as the Sunpak 2X Neutral Density filter or the Tiffen Neutral Density filter (available in densities of 0.3, 0.6, and 0.9) will let you do either without affecting color balance or color accuracy.
Special Effects Filters: Instant Hollywood FX in your camera bag
The range of special effects possible with optical glass filters is virtually limitless, and the ability to add a precise, repeatable, predetermined effect as you’re taking the picture by simply screwing a filter into your lens is simply liberating. It’s clearly impossible to detail every type of special effects filter in this limited space but check out the extensive lines of the major filter manufacturers such as Tiffen, B&W, Heliopan, Adorama, Hoya, etc. on the Adorama website and you’ll be sure to find what you want at reasonable prices. We’ve included before and after images shot the exclusive Tiffen Enhancing Filter, a unique filter that intensifies reds, rust browns, and oranges while having a minimal effect on other colors. It’s perfect for shooting fall foliage, rock formations, and provides even more dramatic effects when it’s combined with a polarizer.