Successful photographers and artists have an intimate understanding of the importance of light in shaping an image. Rembrandt was a master of using light to create moods and reveal the character of his subjects. The late artist Thomas Kinkade’s official tagline was “Painter of Light.” Dean Collins, co-founder of Finelight Studios, revolutionized how a whole generation of photographers learned and used lighting. It’s impossible to underestimate how the use of light adds to—and how misuse can detract from—your photographs.
All forms of visual art use light to shape the finished product. Sculptors don’t have control over the light used to illuminate their finished work, so they must create shapes using planes and curved surfaces so that the form envisioned by the artist comes to life from a variety of viewing and lighting angles. Painters, in contrast, have absolute control over both shape and light in their work, as well as the viewing angle, so they can use both the contours of their two-dimensional subjects and the qualities of the “light” they use to illuminate those subjects to evoke the image they want to produce.
Photography is a third form of art. The photographer may have little or no control over the subject (other than posing human subjects) but can often adjust both viewing angle and the nature of the light source to create a particular compelling image. The direction and intensity of the light sources create the shapes and textures that we see. The distribution and proportions determine the contrast and tonal values: whether the image is stark or high key, or muted and low in contrast. The colors of the light (because even “white” light has a color balance that the sensor can detect), and how much of those colors the subject reflects or absorbs, paint the hues visible in the image.
As a Sony photographer, you must learn to be a painter and sculptor of light if you want to move from taking a picture to making a photograph. This chapter provides an introduction to using the two main types of illumination: continuous lighting (such as daylight, incandescent, or fluorescent sources) and the brief, but brilliant snippets of light we call electronic flash.
Continuous lighting is exactly what you might think: uninterrupted illumination that is available all the time during a shooting session. Daylight, moonlight, and the artificial lighting encountered both indoors and outdoors count as continuous light sources (although all of them can be “interrupted” by passing clouds, solar eclipses, a blown fuse, or simply by switching off a lamp). Indoor continuous illumination includes both the lights that are there already (such as incandescent lamps or overhead fluorescent lights indoors) and fixtures you supply yourself, including photoflood lamps or reflectors used to bounce existing light onto your subject.
The surge of light we call electronic flash is produced by a burst of photons generated by an electrical charge that is accumulated in a component called a capacitor and then directed through a glass tube containing xenon gas, which absorbs the energy and emits the brief flash. Electronic flash is notable because it can be much more intense than continuous lighting, lasts only a brief moment, and can be much more portable than supplementary incandescent sources. It’s a light source you can carry with you and use anywhere.
Indeed, your Sony a6000 comes with a built-in flash unit, shown elevated in Figure 10.1. Like all small flash tubes, this one is seriously underpowered. If you’re using the kit lens set to f/3.5, with an ISO 100 setting, the maximum flash range is about 5.6 feet. Effectively, that means you’ll need to use ISO settings much higher than ISO 100 to use the flash. At ISO 1600, for example, the flash range extends to a more reasonable 22.4 feet. When you boost the ISO, the range increases because of greater sensor sensitivity.
Figure 10.1 One form of light that’s always available is the built-in flash on your a6000.
Since we do not usually want to shoot at very high ISO where digital noise can degrade image quality, the built-in flash is not ideal for all purposes. It’s best reserved for fill-in flash to illuminate inky shadows in outdoor photography (where less power is required to achieve that effect), or for close-up photography in low light.
Before moving on to discussing flash in detail, let’s review the advantages and disadvantages of each type of illumination. Here’s a quick checklist of pros and cons:
Figure 10.2 You always know how the lighting will look when using continuous illumination.
The inverse square law, first applied to both gravity and light by Sir Isaac Newton, dictates that as a light source’s distance increases from the subject, the amount of light reaching the subject falls off proportionately to the square of the distance. In plain English, that means that a flash or lamp that’s 12 feet away from a subject provides only one-quarter as much illumination as a source that’s 6 feet away (rather than half as much). (See Figure 10.3.) This translates into relatively shallow “depth-of-light.” That’s why your built-in flash can only be used at close distances.
In flash photography, your a6000’s shutter speed (called sync speed in flash photography) is set to 1/160th second, but when flash is the primary light source, the effective exposure time will be the 1/1,000th to 1/50,000th second or less; this is the actual duration of the flash illumination. As you can see in Figure 10.4, it’s possible to freeze motion with flash of very short duration. The only fly in the ointment is that, if the ambient light is strong enough, it may produce a secondary “ghost” exposure, as I’ll explain later in this chapter.
Figure 10.3 A light source that is twice as far away provides only one-quarter as much illumination.
Figure 10.4 Electronic flash can freeze almost any nearby motion because of its extremely short duration.
But indoors, the reduced illumination quickly has you pushing your a6000 to its limits. For example, if you’re shooting indoor sports in a dark arena, there probably won’t be enough available light to allow you to use a 1/2,000th second shutter speed unless you use a lens with an extremely wide aperture (such as f/1.8) or set a very high ISO where image quality can suffer. (In truth, the gym where I shoot indoor basketball allows me to do so at 1/500th second at f/4 using ISO 1600.) In many indoor sports situations, you may find yourself limited to a shutter speed of 1/500th second or slower.
While continuous lighting and its effects are generally much easier to visualize and use than electronic flash, there are some factors you need to take into account, particularly the color temperature of the light. (Color temperature concerns aren’t exclusive to continuous light sources, of course, but the variations tend to be more extreme and less predictable compared to electronic flash.)
Color temperature, in practical terms, is how “bluish” or how “reddish” the light appears to the digital camera’s sensor. Indoor illumination is often quite warm, comparatively, and appears reddish to the sensor. Daylight, in contrast, especially on an overcast day, seems much bluer to the sensor. Our eyes (our brains, actually) are quite adaptable to these variations, so white objects don’t appear to have an orange tinge under a tungsten lamp or a blue tint on a cloudy day. Yet, these color temperature variations are real and the camera will record them unless you use an appropriate white balance setting.
It’s important to be aware of the color temperature of the light when you want to get an accurate overall color balance (or white balance)—either using the White Balance system’s smarts or making manual settings, using your own knowledge and experience. Color temperature can be confusing, because of a seeming contradiction in how color temperatures are named.
We are all more familiar with the concept of ambient temperatures in the Arctic (low equaling cold) and at the equator (high or warm), but color temperature measurements (in degrees Kelvin) use the opposite approach. The lower numbers indicate warmer (reddish) light, while the higher numbers refer to cooler (bluer) light. It might not make sense to say that 3,400K is warmer than 6,000K, but that’s the way it is. If it helps, think of a glowing red ember contrasted with a white-hot welder’s torch, rather than fire and ice.
The confusion comes from physics. Scientists calculate color temperature from the light emitted by a mythical object called a black body radiator, which absorbs all the radiant energy that strikes it, and reflects none at all. Such a black body not only absorbs light perfectly, but it emits it perfectly when heated (and since nothing in the universe is perfect, that makes it mythical).
At a particular physical temperature, this imaginary object always emits light of the same wavelength or color. That makes it possible to define color temperature in terms of actual temperature in degrees on the Kelvin scale that scientists use. Incandescent light (from a light bulb that’s not daylight balanced), for example, typically has a color temperature of 2,700K to 3,000K. If a room is lit only by candles, the color temperature will be in the 1,000K to 2,000K range. Outdoors in daylight however, the color temperature might range from 5,500K to 6,000K. Each type of illumination we use for photography has its own color temperature range—with some cautions. The next sections will summarize everything you need to know about the qualities of these light sources.
Daylight is produced by the sun, and so is moonlight (which is just reflected sunlight). Daylight is present, of course, even when you can’t see the sun. When sunlight is direct, the illumination can be bright and harsh. If daylight is diffused by clouds, softened by bouncing off objects such as walls or your photo reflectors, or when filtered by shade, it can be much dimmer and less contrasty.
Daylight’s color temperature can vary quite widely. It is highest (most blue) at noon when the sun is directly overhead, because the light is traveling through a minimum amount of the filtering layer we call the atmosphere. The color temperature at high noon may be around 5,500K to 6,000K. Earlier and later in the day, the sun is lower in the sky and the particles in the air provide a filtering effect that warms the illumination to about 4,500K on a sunny day. (If clouds completely cover the sun, the color temperature will be around 7,000K, slightly blue.) Starting an hour before dusk and for an hour after sunrise, the warm appearance of the sunlight is even visible to our eyes, as shown in Figure 10.5; in such conditions, the color temperature may dip to around 4,500K and even to 3,200K.
Because you’ll be taking so many photos in daylight, you’ll want to learn how to use or compensate for the brightness and contrast of sunlight, as well as how to deal with its color temperature. I’ll provide some hints later in this chapter.
Figure 10.5 At dawn and dusk, the color temperature of the sunlight will dip to 4,500K or even to 3,200K depending on the atmospheric conditions.
The term incandescent or tungsten illumination is usually applied to the direct descendents of Thomas Edison’s original electric lamp. Such lights consist of a glass bulb that contains a vacuum, or is filled with a halogen gas, and contains a tungsten filament that is heated by an electrical current, producing photons and heat. Tungsten-halogen lamps are a variation on the basic light bulb, using a more rugged (and longer-lasting) filament that can be heated to a higher temperature; it’s housed in a thicker glass or quartz envelope, and filled with iodine or bromine (“halogen”) gases. The higher temperature allows tungsten-halogen (or quartz-halogen/quartz-iodine, depending on their construction) lamps to burn “hotter” and whiter. Used for many automobile headlamps today, they’ve also been popular for photographic illumination.
Although a tungsten flood lamp intended for photography isn’t a perfect black body radiator, it’s close enough that the color temperature of the light it emits can be precisely calculated (about 3,000K to 3,550K, depending on the type of lamp). With this type of lighting, there’s little concern about color variation, at least, until you get very close to the end of the lamp’s life. By comparison, the tungsten (incandescent) light bulbs intended for household use can vary in color temperature, and these days, many such bulbs are rated as “White” or “Daylight Balanced;” this indicates a modification that causes the light output to be bluer, closer to 5,500K to 6,000K, depending on the bulb.
The other qualities of this type of lighting, such as contrast, are dependent on the distance of the lamp from the subject, type of reflectors used, and other factors that I’ll explain later in this chapter.
Fluorescent light has some advantages in terms of illumination, but some disadvantages from a photographic standpoint. This type of lamp generates light through an electro-chemical reaction that emits most of its energy as visible light, rather than heat; that’s why the bulbs don’t get as hot. The type of light produced varies depending on the phosphor coatings and type of gas in the tube. So, the illumination produced by fluorescent tubes or bulbs can vary widely in its characteristics.
That’s not great news for photographers. Different types of lamps have different “color temperatures” that can’t be precisely measured in degrees Kelvin, because the light isn’t produced by heating. Worse, fluorescent lamps have a discontinuous spectrum of light that can have some colors missing entirely. A particular type of tube can lack certain shades of red or other colors (see Figure 10.6), which is why fluorescent lamps and other alternative technologies such as sodium-vapor illumination can produce ghastly looking human skin tones. Their spectra can lack the reddish tones we associate with healthy skin and emphasize the blues and greens popular in horror movies.
Figure 10.6 The fluorescent lighting in this huge indoor arena added a distinct greenish cast to the image.
I showed you how to adjust white balance in Chapter 3.
In most cases, however, the a6000 will do a good job of calculating white balance for you, so Auto can be used as your choice most of the time. Use the preset values or set a custom white balance that matches the current shooting conditions when you need to. The only really problematic light sources are likely to be fluorescents. Vendors, such as GE and Sylvania, may actually provide a figure known as the color rendering index (or CRI), which is a measure of how accurately a particular light source represents standard colors, using a scale of 0 (some sodium-vapor lamps) to 100 (daylight and most incandescent lamps). Daylight fluorescents and deluxe cool white fluorescents might have a CRI of about 79 to 95, which is perfectly acceptable for most photographic applications. Warm white fluorescents might have a CRI of 55. White deluxe mercury vapor lights are less suitable with a CRI of 45, while low-pressure sodium lamps can vary from CRI 0-18.
Remember that if you shoot RAW format photos with the a6000, you can set any desired white balance for an image in the converter software whether you use the Sony Image Data Converter SR, Photoshop, Photoshop Elements, or another image editor that supports the Sony RAW format. While color-balancing filters that fit on the front of the lens still exist, they are primarily useful for film cameras, because film’s color balance can’t be tweaked as extensively as that of a sensor.
Until you delve into the situation deeply enough, it might appear that serious photographers have a love/hate relationship with electronic flash. You’ll often hear that flash photos are less natural looking, and that on-camera flash in most cameras should never be used as the primary source of illumination because it provides a harsh, garish look. Some photographers strongly praise available (“continuous”) lighting while denouncing electronic flash.
In truth, however, the bias is against bad flash photography. Indeed, flash—often with light modifier accessories—has become the studio light source of choice for pro photographers. That’s understandable, because the light is more intense (and its intensity can be varied to order by the photographer), freezes action, frees you from using a tripod (unless you want to use one to lock down a composition), and has a snappy, consistent light quality that matches daylight. (While color balance changes as the flash duration shortens, some Sony flash units can communicate to the camera the exact white balance provided for that shot.) And even conservative photographers will concede that electronic flash has some important uses as an adjunct to existing light, particularly to fill in dark shadows.
But electronic flash isn’t as inherently easy to use as continuous lighting. As I noted earlier, flash units are more expensive and they don’t show you exactly what the lighting effect will be, unless you use a second source such as the rudimentary pulsed light called a modeling light (discussed earlier) for a preview of limited value. As well, when you’re using several electronic flash units, the exposure can be more difficult to calculate accurately than it would be with continuous light.
Electronic flash illumination is produced by a flash of photons generated by an electrical charge that is accumulated in a component called a capacitor and then directed through a glass tube containing xenon gas, which absorbs the energy and emits the brief flash. For the built-in flash furnished with the camera, the full burst of light lasts about 1/1,000th second, and provides enough illumination to shoot a nearby subject, unless you’re using a wide aperture and/or a high ISO level as discussed earlier. As you can see, the built-in flash is relatively underpowered and not your best choice when photographing distant subjects.
The a6000’s built-in flash is always available as required. There are several flash modes available in the Camera Settings 2 menu:
Figure 10.7 The owl (left) was in shadow. Fill-flash (right) brightened up the bird, while adding a little catch light to its eye.
Figure 10.8 With front (first) curtain sync, the ambient light ghost image appears in front of a moving object. With rear (second) curtain sync, the ghost image trails behind the subject’s motion.
The built-in flash is a handy component because it is available as required, without the need to carry an external flash around with you constantly. This section explains how to use the flip-up flash. Start by pressing the flash button (on the center edge of the back of the camera). Use the P, A, S, or M mode to ensure that all flash features will be available.
BOUNCE FLASH
Although the built-in flash doesn’t have detents to allow variable angles, you can easily tilt it with the tip of your index finger while shooting to provide additional flexibility. For example, you can carefully angle the flash downward when shooting close-ups (perhaps with mixed results), or tilt it backward to bounce it off a ceiling or other diffusing surface. Of course, the light may not actually reach the subject; you would need to use a high ISO (to increase sensor sensitivity) for this technique to provide any effect. Of course, if the ceiling is low or you’re bouncing the light off a large white sheet of cardboard—and the subject is close to the camera—it may work well when using ISO 800 or higher.
This is a feature discussed previously in Chapter 3. It’s important to keep in mind how the a6000’s exposure compensation system works when you’re using electronic flash. To activate exposure compensation for flash, visit the Flash Comp. item in the Camera Settings 2 menu and set the amount of plus or minus compensation you want. This function is not available when using Auto or SCN modes or Panorama mode. When you find that your flash photos are too dark even after you have set +2, then the flash simply cannot provide more power; you must move closer to the subject, or use a wider aperture, or set a higher ISO, or take all of these steps. Note too that when a subject is extremely close to the camera, even a –2 setting may not prevent an excessively bright image.
Flash exposure compensation affects only the amount of light emitted by the flash. If you want to adjust the brightness of the ambient light exposure, you would also need to use the conventional exposure compensation feature. In fact, you can use both features at the same time, to get a brighter subject and a darker background, or vice versa. Let’s say you’re taking a photo of a friend posing against a light-toned background such as a white cabana on a beach. A plus exposure compensation setting (perhaps +1 when using multi-segment metering) will ensure that the cabana won’t be underexposed while a –1/3 or –2/3 flash exposure compensation will ensure that shadows on your friend’s face will be lightened by a very gentle burst of flash. This is an advanced technique that requires some experimentation but can be valuable when used with some expertise.
When using semi-automatic or manual exposure modes (or any SCN mode in which flash is used), red-eye reduction is available if Red Eye Reduction is On in the Camera Settings 2 menu (as described in Chapter 3). The flash will fire a burst before the photo is actually taken as you depress the shutter release button. That will theoretically cause your subjects’ irises to contract (if they are looking toward the camera), thereby reducing the red-eye effect in your photograph. This option is not available when using Rear Sync.
Sony currently offers several accessory electronic flash units that are compatible with the Alpha cameras with an accessory or multi interface shoe. Note that older flash units using the original Minolta/Sony proprietary accessory shoe require an inexpensive adapter (about $15) to fit the newer multi interface shoe. These external units can be mounted on the camera or used off-camera with wireless connectivity when triggered by another external flash. Not all the models I describe in this chapter may be available from Sony; some may be discontinued but still widely sold either in new or mint used condition from various retailers.
The beefiest Sony model, the HVL-F60M (shown in Figure 10.9) sells for $550 in the US. It offers very high power output and a vast range of features, including a modeling light and a quick shift bounce design which makes shifting between horizontal and vertical shooting particularly convenient. The HVL-F43AM ($350) and the discontinued HVL-F58AM also offer the quick shift bounce feature. (The F58AM was full-featured but the newer model offers some benefits, including slightly higher power output and a built-in LED video light.)
Bouncing is particularly convenient and effective with Sony’s unique quick shift bounce system. This configuration is particularly effective when shooting vertical pictures. With most other on-camera external flash units, as soon as you turn the camera vertically, the flash is oriented vertically, too, whether you’re using direct flash or bouncing off the ceiling (or, wall, when the camera is rotated). A Sony flash with quick shift bounce is equipped with a clever pivoting system that allows you to re-orient the flash when the camera is in the vertical position, so flash coverage is still horizontal, and can be tilted up or down for ceiling bounce.
Figure 10.9 The Sony HVL-F60AM is the top-of-the-line external flash unit and includes a bonus, LED lights for video.
A very inexpensive and useful unit, the $149 HVL-F20AM (shown in Figure 10.10) is compact and can be folded down when not in use; naturally, it’s not very powerful. Sony also markets flash units for extreme close-up photography with a macro lens, the HVL-RLAM Ring Light and the HVL-MT24AM Macro Twin Flash Kit; since these are specialized products, I won’t discuss them.
Wireless flash triggering is another topic beyond the scope of this book; the a6000’s built-in flash can’t trigger an external Sony flash unit. So, at the very least, you must have an external flash mounted in the multi interface shoe and a second external flash that the mounted flash can trigger wirelessly.
This $550 flagship of the Sony accessory flash line is the most powerful unit the company offers, with an ISO 100 guide number (GN) of 60 in meters or 197 in feet at ISO 100. The GN does not indicate actual flash range, but it’s useful when comparing several flash units in terms of their general power output.
Guide numbers are a standard way of specifying the power of a flash when used in manual, non-autoexposure mode. Divide the guide number by the distance to determine the correct f/stop to use at full power. With a GN of 197, you would use an aperture of around f/19.5 for a subject that’s 10 feet from the camera (197 divided by 10), or around f/9.5 for a subject at a distance of 20 feet. The Guide Number data is most useful for comparing the relative power of several flash units that you’re considering. According to the Inverse Square Law, a flash unit with a GN of 200 in feet puts out four times the amount of light as one with a GN of about 100 in feet. If your accessory flash has a zoom head, the GN will vary according to the zoom setting.
Like all the Sony flash units except the HVL-F20AM, the F60AM automatically adjusts the head to suit the lens focal length in use. You can zoom the head manually instead, if you prefer. A built-in slide-out diffuser panel boosts wide-angle coverage so it’s suitable for photos taken at short focal lengths with the 10-18mm zoom. There’s also a slide-out “bounce card” that can reflect some light forward even when bouncing the flash off the ceiling, to fill in shadows or add a catch light in the eyes of your portrait subjects. This dust and moisture resistant 21 ounce unit uses four AA batteries but can also be connected to the FA-EB1AM external battery adapter (you just blew another $190), which has room for 6 AA batteries for increased capacity and faster recycling.
The F60AM automatically communicates white balance information to your camera, allowing the Alpha to adjust WB to match the flash output. It also offers a dedicated video light that can be useful for a bit of extra illumination if the subject is close to the camera.
You can use this large unit as a main flash, or allow it to be triggered wirelessly by another compatible flash unit. A pre-flash burst of light from the triggering unit (the built-in flash or an on-camera HVL unit) causes a remote flash unit to fire. When using flash wirelessly, Sony recommends rotating the unit so that the flashtube is pointed to the location where light should be directed, while the front (light sensor) of the flash is pointed toward the camera. In wireless mode, you can control up to three groups of flashes, and specify the output levels for each group, giving you an easy way to control the lighting ratios of multiple flash units.
This flash unit can provide a simulated modeling light effect at two flashes per second or at a more useful (but more power-consuming) 40 flashes per second for 4 seconds for 160 continuous mini-bursts. In wireless off-camera flash, the HVL-60M can function as the main (on-camera) flash in wireless mode or it can be the remote flash, triggered wirelessly by another compatible flash unit, as discussed earlier.
Those who are frustrated by an inability to use a shutter speed faster than 1/160th second will love the High Speed Sync (HSS) mode that allows for flash at 1/500th to 1/4,000th second! (HSS is also available with the HVL-F43AM and the discontinued HVL-58AM and HVL-F36AM.) This is ideal when you want to use a very wide aperture for selective focus with a nearby subject with flash; HSS at a fast shutter speed such as 1/1,000th second is one way to avoid overexposure. The mode button on the back of the flash is used to choose either TTL or Manual flash exposure. You can then use the Select button and plus/minus keys to activate HSS mode; HSS appears in the unit’s data panel as confirmation of the mode.
Keep in mind that flash output is much lower in High Speed Sync than in conventional flash photography. That’s because less than the full duration of the flash is used to expose each portion of the image as it is exposed by the slit passing in front of the sensor. As a result, the effective flash (distance) range is much shorter.
In addition, HSS will not work when using multiple flash units or when the flash unit is set for left/right/up bounce flash or when the wide-angle diffuser is being used. (If you’re pointing the flash downward, say, at a close-up subject, HSS can be used.)
This less pricey ($350, but discontinued) electronic flash shares many of the advanced features of the HVL-F58AM, but has a lower guide number of 43/138 (meters/feet). (By now, you’ve figured out that the model number of Sony’s electronic flash units represent the GN in meters, such as the 43 for this model.) Features shared with the high-end unit include HSS, automatic white balance adjustment, and automatic zoom with the same coverage of focal lengths and the slide-out diffuser as well as a built-in bounce card. This unit also can be used in wireless mode in the same manner and it also offers the quick shift bounce feature. The HVL-F43AM is a tad lighter than its bigger sibling, at 12 ounces and runs on four AA’s.
Overall, this is my favorite flash unit for my a6000. Introduced in 2014 for about $400, this versatile flash has a guide number of 43/141 (meters/feet), like its predecessor, with wireless TTL operation as both a master controller and remote flash. You can wirelessly adjust flash ratios to tweak output levels of three different flash groups. It also has an LED video light, with 10 different intensity levels, and “modeling flash” capabilities to give you a long-lasting preview burst of up to four seconds. Manual flash control operates from full power to 1/128th power in 1/3 or 1/2EV steps.
Although discontinued, you can easily find this versatile flash available online or in used condition. The guide number for this lower-cost Sony flash unit is (surprise!) 36/118 (meters/feet). Although (relatively) compact at 9 ounces, you still get some big-flash features, such as wireless operation, auto zoom, and high-speed sync capabilities. Bounce flash flexibility is reduced a little, with no swiveling from side to side and only a vertical adjustment of up to 90 degrees available; HSS is supported.
Featuring premium features in a compact size, the HVL-F32M External Flash from Sony is an auto/manual flash unit that offers flexible lighting control and is compatible with Sony’s Multi-Interface shoe. It features a retractable 16mm wide-angle panel, as well as a built-in bounce sheet that can be used even when shooting vertically—without changing the angle of reflected light.
Introduced just as I was finishing this book, the $299 HVL-F32M is Sony’s newest electronic flash unit and has the same Multi-Interface shoe as the a6000, so it needs no adapter to mount. It features a high-speed synchronization mode, wireless control, and automatic white balance compensation. The flash is powered by a pair of AA batteries and it is resistant to both dust and moisture. Those who love to use bounce flash will like the built-in bounce sheet, and retractable wide-angle panel that spreads the light to cover the equivalent of a 16mm lens.
The least expensive Sony flash (see Figure 10.10) is this one ($150), designed to appeal to the budget conscious, especially those who need just a bit of a boost for fill flash, or want a small unit (just 3.2 ounces) on their camera. It has a guide number of 20 at ISO 100, and features simplified operation. For example, there’s a switch on the side of the unit providing Indoor and Outdoor settings (the indoor setting tilts the flash upward to provide bounce light; with the outdoor setting, the flash fires directly at your subject). There are special modes for wide-angle shooting (use the built-in diffuser to spread the flash’s coverage to that of a lens with a very wide field of view or choose the Tele position to narrow the flash coverage to that of a 50mm or longer lens for illuminating more distant subjects). While it’s handy for fill flash, owners of an a6000 will probably want a more powerful unit as their main electronic flash.
Figure 10.10 The HVL-F20AM flash unit is compact and inexpensive.
You may not use your flash very often, but when you do, you want it to operate properly. The problem with infrequent flash use is that conventional nickel-metal hydride batteries lose their charge over time, so if your flash unit is sitting in your bag for a long time between uses, you may not even be aware that your rechargeable batteries are pooped out. Non-rechargeable alkaline cells are not a solution: they generally provide less power for your flash, and replacing them can be costly. The Energizer Lithium Ultimate AA batteries last up to three times longer, but they sell for about $10 for four.
I’ve had excellent luck with a new kind of battery developed by Panasonic called eneloop cells. They retain their charge for long periods of time—as much as 75 percent of a full charge over a three-year period (let’s hope you don’t go that long between uses of your flash). They’re not much more expensive than ordinary rechargeables, and can be revitalized up to 1,500 times. They’re available in capacities of 1500mAh to 2500mAh. I use the economical models with 1900mAh capacity.
