We Maintain That The Single Most Important Acces Sory For

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We maintain that the single most important acces­ sory for your DSLR is a full-featured TIL flash unit With "lightning in a bottle," you can freeze action solid, mimic studio lighting, tame harsh midday sunlight, balance (or unbalance) the color in a scene, ; and produce wild and weird effects-with no soft­ ~ ware required. Here we present a primer on portable ~ flash theory and practice. By Dan Richards AD flash photos are double exposures. The two exposures occur simulta­ neously. one by the ambient light. the other by the flash illumina­ tion. You can vary each of the exposures for a wide variety of different effects: You can make them ofequal brightness. a little unequal. or widely unequal you can give them different color balances; you can even vary shutter effects, with one exposure motion-blurred and the other tack-sharp. This is what makes flash photography so much fun­ and so supremely useful. ~ V EXPERIMENTlIf you're shooting, say, a foreground subject against a sunset or leafy background, don't settle for the auto settings. Vary both the ambient and ftash exposure to see different effects. Adjusting the aperture &fleets both ambient and flash exposure. 2 As the aperture is the lens's light valve, opening it up or stopping it down will lighten or darken both exposures-provided the flash out­ put is kept at the same level. (With the flash set to auto, it will compen­ sate by increasing or reducing the output-more on this below.) Since a large aperture admits a lot oflight, the flash can emit less for proper exposure. This will give you greater flash reach and/or longer battery life. Asmall aperture requires more light, and your reach and/or battery will suffer accordingly ~ USING A WIDE aperture to V limit depth of field In an outdoor ~It? In bright light, this may fon:e you to exceed your camera's maximum sync speed (see sidebar, page 118). Solution: a neutrakienslty (NO) filter to reduce the light entering the lens. A &-stop (NO 1.8) filter will let you ltos drop to j,/250 sec from j,/SOOO sec, atthough optical viewing will be dim and autofocus dicey. 3 Shutter~ affects ambient but not flash exposure. The flash is a very brief burst occurring during the relatively longer duration of the shutter opening-a flash burst of V2000 sec will provide the same illumination with a shutter speed Bounce flash can eat up flash power-not just because of the extra distance the light must travel, but also because even quite reflective walls or ceilings absorb some of the light If your bounce shots are turning out under­ exposed, open up the aperture. .of 1/30 sec as it will with a 1/250 sec shutter. So you can lighten or darken the ambient exposure by increasing or reducing the shutter speed while maintaining the same aperture-and thus the same flash output. G lOUCANVAff'{theshutter speed and still use autoexposure by setting the camera to aperture­ priority mode. Now, when you da~ or bl1ghten with exposure compensation, the camera will vary the shutter speed but keep the aperture the same. For natural­ looking fill flash, underexpose the flash exposure. 4 The idea behind natural fill is to make it look like soft ambient light. As fill flash is ordinarily used for back- or sidelit sub­ jects, setting the flash illumina­ tion to the same level as the ambient light makes your strobe obvious. To keep it subtle, use the flash's exposure compen­ sation to dial down its output. Settings in a range of -0.7 to -2 EV usually work well. ~ DONT FEAR ·unnatural" fill. For example, a 2-stop ambient underexposure combined with full ftash exposure can dramatically isolate a human figure or foreground object. V 5 Flesh has color. While we think of flash as white light, flash, like all visible light, has a color cast. Accessory flash manu­ facturers set "daylight balance" at around 5200-5500 degrees Kelvin in color temperature. This is actu­ ally a good deal warmer in color than daylight on a blue-sky day, when color temperature can go as agh as 10,000 degrees K(very blue), leading to a mismatch in color balance. This is why digital cameras have separate presets for flash and daylight white balance. Amore common mismatch: flash with tungsten room light. With a digital camera set to flash white balance, the foreg:~und subject will appear a netM'a1 color while background illumination out of the range of the flash will have a yellow-red cast. (Many photographers like this look and the amblent light and/or ambient WithAA exposure low, though, or you might batteries, just capture a ghost-the term for there is no ambient motion blur in a flash shot. free lunch: The batteries TrL flash works better with the that give camera in manual you the exposure mode. shortest By setting the ambient exposure recycling you want manually, you eliminate times,NiMH one variable and can concentrate rechargeables, on the effects of various flash exposures, positions, etc. Say give you the you're shooting a series of por­ fewest shots traits outdoors with fill flash. You per charge; want an ambient exposure that the ones keeps the background at a certain that give light level, but with the camera' you the set to auto, it might keep adjusting this exposure as you change most shots, position, focal length, or flash disposable output. Better to lock it in using lithiuInS, manual mode. have the ~ WITH flU FLASH In a backlit longest V situatIon, it's often better to recycling set the ambient exposure 1 stop or times. Alkaline a little more over the meter reading. This makes the backlighting appear AAsland more realistic. With portraits, it also in between. helps to obscure background detail. 7 set it up deliberately) Flip the camera's white balance to tung­ sten, and the background light will shift to neutral while the fore­ ground subject appears very blue. Want to even the balance? Put an amber filter over the flash lens, and set the camera to tungsten or auto white balance. ~ Willi FILM, you may V need to add an extra step to color balancing. Shooting daylight film under fluorescent lights, you would put a green gel (CC 30) over the flash head to balance It with the greenish f1uorescents. You'd then place a magenta filter (such as the ntfen Fl-D) over the camera lens to neutralize the now-overall green cast. Autoflash varies the duration of the flash. Modem accessory flash units automate exposure by reading the bounce back of the flash 70 POPULAR PHOTOGRAPHY through the lens (TTL). (Many units now make this reading via a brief preflash.) The camera/flash brain adjusts the flash exposure by making the burst shorter or longer for less or more light, respectively The range of flash bursts is pretty astounding---a typi­ cal accessory unit may have durations from 1/1000 sec to 1/50,000 sec or even less. You also adjust manual flash power by changing duration, almost always measured in frac­ tions: full power, 112, 1/4, 1/8, etc., often down to 1/64 power for the shortest flash duration. USE VERY BRIEF flash G duratlons for extreme motion­ stopping photos. Positioning the flash close to your subje<:t, using a wide aperture, and setting a high ISO will all shorten the duration of autoflash, and you can dial In hIgh speed manually, too. Keep Flash follows the same hardnessl softness rules as ambient light. The broader the light source, the softer the light. That's why studio portraits shooters use softboxes, umbrellas, and beauty dishes on their strobes. But the narrower the light source, the harder the light. So studio shooters use snoots and grids to get hard, even harsh, effects. Placing the light source closer to your subject makes it broader and therefore softer; mov­ ing the light source farther away makes it narrower and harder. Read all about the qualities of light in "10 Things You Must Know About Light" in our May 2010 issue or at PopPhoto.comllighting-facts. CONnNIJ£S ON PAGJ: 118 ~WIRELESS FLASH J CONTINUED FROM PAGE 65 - MANFROTTO'S 50018 NANO ST ND. Almost every­ one int. 'ewed agreed this lightstand is the one best suited for use with shoe-mount flashes. More than 6 feet tall, it folds up small and weighs just 2 pounds. ($50, street; www.manfrotto.com) - GARY FONG'S UNIVERSAL UGKTSPHERE. This softens li~t, but if you remove its dome, you can selectively apply hard light, too. ($38, street; www.garyfong estore.com) -STlCKYFILTERS. Sized for shoe-mount or pop-up flash heads, Stickyfilters are adhe­ sive, color-balancing gels that slap into place and stay there. ($30-$50, depending on size; stickyfilters.com) Ready to take your flash off­ camera? Photographers who've done it successfully offer the same advice: Read and reread your flash manual; practice and master flash features (such as high-speed syncing) individ­ ually, then attempt to combine them in a wireless, off-camera setup. Also take advantage of the many resources out there such as the Canon Digital Learning Center, Sly Arena's Speedliter's Handbook, Nikon's Creative Lighting System sup­ port materials, flash photogra­ phy workshops, and websites such as Strobist.com. Finally, practice and master these off-camera flash tech­ niques in your living room using inanimate objects or a willing friend as your subject. When you've nailed the techniques, stand back and enjoy the transformative impact that off­ camera wireless flash can bring to your photography. 0 118 POPULAR PHOTOGRAPHY OCTOBER 2011 '"WIRES ARE FOR CHUMPS," declares ArIzona pro Bruce Dom, maker of the fast.­ Ion portrait on page 60. It you agree and haven't yet taken the wireless plunge, you have some decisions to make. Am and foremost Is how to go wireless: with an Infrared or radio system. Infrared systems such as those made by canon and Nlkon communicate using pul­ sating beams of light that travel In a direct line of sight between a camera-based transmitter and ftash-based receiver. Radio systems such as the popular Pock­ etWJzards, on the other hand, transmit thelr data via electromagnetic waves. They don't require direct line of sight, but can comm~ nlcate around comers, through walls, and across much further distances that Ilght­ based triggers. The big flash makers have cast thelr lot with Infrared systems. For one thing, laws regulating radio transmissions and their usable frequencies are different around the world. Infrared Is also generally less expensive than radio and often offers exposure control. For those two reasons alone, Irs great for beginners. Many flash units have built-In Infrared receivers so you need only pur­ chase a transmitter. The downsides, besides the line of sight Issue, are that IR receivers can have dlfftculty reading transmissions In bright daylight (To minimize the problem, when setting up, don't aim the receiver so It looks m RADIO Quantum Fl88Xwlre flash trigger (.184, etlMtfor ........ -, ...... ) sou 1Bre to It directly Into the sun.} Also, thelr range Is limited to between 10 and 40 feet, depend­ Ing on the condItIor5, and some flash feature&--5eCOnd curtain syncing. for ~m­ p1e--aren't supported by IR technology. To get the greatest possible distance from an Infrared setup, make sure the transmitter and receiver are aimed at each other, and, It necessary, mcwe the transmitter closer to the receiver/flash combo with the help of a m extension cord, such as those sold by OCF Gear (www.ocfgear.com). Radio systems, on the other hand, can operate across hundreds of feet, but are subject to electronic Interference and many do not offer exposure control. The Interference can come from other photog­ raphers UsIng the same system, or from ambient sources of eIectromagnetlc energy. The well-known wedding photogI'apher and photo entrepreneur KevIn Kubota lists con- m and m~ 81M If go 111 phO seIII com tane • RIll rec:e atta ... The! flail and tiler ~ Sou but RADIO PhotDfIex RashFire transmttblr/ receherldt (UOO, etIMt) POI