A couple of years ago, there were relatively few Sony E-mount lenses for mirrorless cameras with the typical size (16.5 × 23.5mm) sensor. The situation has significantly improved with additional models released by Sony, Zeiss, and other vendors. Of course, in another sense, there are dozens of lenses that will work reasonably well with the a6000, even if they weren’t specifically made for it. Any of the Sony AF or Minolta Maxxum/Dynax A-mount autofocus lenses designed for SLRs or for digital SLT cameras like the A77 ii and A99, can be used with the a6000 if you buy an optional Sony LA-series adapter.
Now that Sony is also making lenses in FE-mount, for the full-frame mirrorless Alpha a7-series, those lenses, too, will work just fine on your camera—although they may be a bit out of the price range of many a6000 owners. You can also find third-party brand adapters that allow for using lenses of entirely different brands (such as Nikon F and Pentax K) on your a6000; these mechanical “couplers” cannot support the camera’s high-tech features and operate only with manual focus. I’ll discuss adapters of all types in detail later in this chapter.
Some recent Sony E-mount lenses are power-zoom-designated, indicating a power zooming mechanism instead of the conventional mechanical zoom. This feature is ideal for use when recording video because the zoom action is so smooth and quiet. The first was the 18-200mm f/3.5-6.3 power zoom OSS, and it is quite large. Subsequently, two smaller power zoom lenses were released, the premium-grade 18-105mm f/4 G power zoom OSS and the more affordable 18-50mm f/3.5-5.6 power zoom OSS; in many countries, the latter is one that’s packaged with the a6000 kit. Most recent is the 18-135mm f/4 G power zoom, an FE mount lens that can be used on both the a6000 and Sony’s full frame a7-series mirrorless cameras.
As I write this, Sony’s E-mount system includes several superb lenses with the Carl Zeiss ZA branding. These are made by Sony to Zeiss specifications and feature the finest optical elements, unusually rugged mechanical aspects and often, wide maximum apertures. My own favorites of these include the Carl Zeiss Vario-Tessar T* FE 24-70mm f/4 ZA OSS; Sony FE 70-200mm F4 G OSS, which I purchased along with my A7r; and the Carl Zeiss Vario-Tessar E f/4 16-70mm ZA OSS lens that came with my a6000. Note too that Zeiss in Germany makes Zeiss Touit lenses in Sony E mount; these are not marketed by Sony, of course. Fortunately, even Sony’s non-Zeiss lenses are excellent. (See Figure 9.1.)
Figure 9.1 A full-range of E-mount lenses, including this Sony FE 70-200mm F4 G OSS work well on the a6000.
From time to time you’ve heard the term “crop factor,” and you’ve probably also heard the term lens multiplier or focal length multiplication factor. While some of these terms are misleading and inaccurate, they’re used to describe the same phenomenon: the fact that cameras like the Sony—and all other digital interchangeable-lens cameras using a sensor smaller than the “full-frame” 24 × 36mm format—provide a field of view (or scene coverage) that’s smaller than you get with a camera employing the larger sensor. The a6000 (as well as numerous other cameras of several brands) uses a sensor that’s 15.6 × 23.5mm in size.
In practical terms, let’s say you’re using a 35mm lens on a full-frame Sony a7r; you get a field of view of 63 degrees. But if you use a 35mm focal length lens on an a6000, the field of view is only 44 degrees because the smaller sensor records only a part of the image that the lens projects. Knowledgeable photographers often discuss this effect as the crop factor and you’ll often find a reference in lens reviews to a focal length equivalent; that’s 1.5X with the sensor size used by a camera like the a6000. In other words, a 35mm lens used on the a6000 is equivalent to a 52.5mm focal length on a full-frame camera like the Alpha SLT-A99. The most accurate expression to describe this concept might be something like field of view equivalency factor.
Figure 9.2 quite clearly shows the phenomenon at work. The outer rectangle, marked 1X, shows the field of view you might expect with a 50mm lens mounted on a full-frame digital model like the a7r or a 35mm film camera, like the 1985 Minolta Maxxum 7000 (which happened to be the first SLR to feature both integrated autofocus and motorized advance, something we take for granted in the digital SLR age). The rectangle marked 1.5X shows the field of view you’d get with that 50mm lens installed on a camera (like most of the Sony Alpha SLTs and all of the Sony mirrorless models other than the A7 series) that uses the more typical 15.6mm × 23.5mm sensor. It’s easy to see from the illustration that the 1X rendition provides a wider, more expansive view, while the other view is, in comparison, cropped.
There’s another way you can look at this. It’s possible to calculate the relative field of view by dividing the focal length of the lens by .667. Thus, a 100mm lens mounted on a Sony has the same field of view as a 150mm lens on a full-frame camera like the A99. We humans tend to perform multiplication operations in our heads more easily than division, so such field of view comparisons are usually calculated using the reciprocal of .667—1.5—so we can multiply instead. (100 / .667=150; 100 × 1.5=150.)
Note
Frankly, all of this is useful only if you were previously using a 35mm SLR and frames of 24mm × 36mm film or a full-frame dSLR like the a7 series. In that case, you might find it helpful to use the crop factor “multiplier” to translate a lens’s real focal length into the full-frame equivalent, even though, nothing is actually being multiplied. If you have always owned a digital camera with a smaller sensor, you already have a good feel as to the field of view that you get at a focal length such as 35mm or 50mm. It’s highly unlikely that you would think in terms that require you to do any calculations.
In any event, I strongly prefer crop factor to focal length multiplier, because nothing is being multiplied (as I said above). A 100mm lens doesn’t “become” a 150mm lens; the depth-of-field and lens aperture remain the same. (I’ll explain more about these later in this chapter.) Only the field of view is cropped. Of course, the term crop factor has a drawback: it implies that a 24 × 36mm frame is “full” and anything else is “less than full.”
I get e-mails all the time from photographers who point out that they own “full-frame” cameras that employ oversized 36mm × 48mm and larger sensors (like the Mamiya 645DF with a Leaf Aptus II digital back, or the Hasselblad H4D-50 medium-format digital camera). By their logical reckoning, the 24mm × 36mm sensors found in full-frame cameras like the Sony a7 series are “cropped.”
Figure 9.2 This image illustrates the field of view provided by a full-frame camera like the Sony a7r (1X) with a 50mm lens, as well as the field of view you’d get when using a camera with the smaller sensor (1.5X crop) like the a6000.
The a6000 is most frequently purchased with a lens, often the retractable 16-50mm f/3.5-5.6 Power Zoom model with OSS, Sony’s Optical SteadyShot Stabilizer discussed in previous chapters. The 16-70mm f/4 Carl Zeiss lens described in the section that follows this one is also popular as an upscale starter optic. (See Figure 9.3.) A zoom is useful but you might prefer the 16mm f/2.8 pancake lens because its minimal size/weight provide great portability that’s ideal while hiking or touring for days while on vacation. Or, if you want a do-everything, walk-around lens, you might want the 18-200mm f/3.5-6.3 OSS zoom. If you already own some lenses for an Alpha SLT-A camera or a Maxxum/Dynax SLR, you might want to just purchase one of two E-mount adapters discussed later and use the lenses you already have.
In this section, I’ll discuss the Sony E-mount lenses, the starter models, as well as the wide-angle lenses. Here are your choices in these categories:
Figure 9.3 This 16-70mm f/4 zoom OSS zoom is very popular since the a6000 is often sold in a kit that includes this lens.
The 16mm lens accepts two add-on accessories that mount on the front, with the VCL-ECF1 fisheye conversion lens ($150) shown in Figure 9.4. It gives you a fisheye view for interesting landscapes, interiors, and other subjects. Given that fisheye lenses are typically used infrequently by most shooters, the low cost of this accessory offsets the less than tack-sharp results you can expect. Mount the five-ounce VCL-ECU1 wide-angle converter ($130) instead, to transform this 16mm lens into a super-wide 12mm (18mm equivalent) lens. I’ve gotten great results from mine, although it works best when the host lens is stopped down at least one or two apertures from wide open.
Figure 9.4 The 16mm “pancake” lens is unusually compact and provides extra compactness, even when equipped with the fisheye attachment shown.
The lenses in the E-mount system range from the sublime to the meticulous, and can prove useful for various kinds of photography. Next, let’s take a look at zooms that extend beyond 100mm and the macro lens. I’ll be covering the high-grade Carl Zeiss ZA series later, but here are your additional E-mount options in the Sony designated line:
A similar lens that’s larger and more expensive ($1,200) because of the power zoom mechanism, the power zoom-designated version (SELP18200) targets a6000 owners who shoot video often and will really appreciate the ability to zoom quietly and extremely smoothly. It’s also equipped with the SteadyShot image stabilizer.
While the Sony-designated E-mount lenses should meet the needs of most photographers, you’ll also find several premium-grade (and expensive) products with the Carl Zeiss ZA designation. The Carl Zeiss models all boast rugged metal construction for great durability, the very effective T* multi-layer anti-reflective coating for flare control, and one or more large high-tech optical elements for effective correction of optical aberrations. Here are my favorite E-mount options for a6000 owners who want the very best:
Figure 9.5 The Carl Zeiss 16-70mm f/4 lens (left) and its 24mm f/1.8 stablemate (right).
A linear stepping motor provides fast, low-noise autofocus that’s ideal when shooting video. Sure, it’s pricey ($1,100), and not exactly compact at 2-3/8 × 2-1/2-inches and nearly 8 ounces, but if you need f/1.8 and its angle of view, nothing else will do the job. This lens can be hard to find since it’s often back-ordered. I have owned mine for over a year now and have gotten excellent results with this superb lens.
Sony makes four A-mount to E-mount adapters, which allow using Sony/Minolta A-mount lenses on an Alpha E-mount camera such as the a6000. Why four different adapters, at four different prices? All four, the LA-EA1, LA-EA2, LA-EA3, and LAEA4, allow connecting an A-mount lens to an NEX/Alpha-series camera. The two odd-numbered adapters use only contrast detect autofocus with lenses that are compatible with them. The two even-numbered adapters have built-in SLT-like phase detection AF systems for faster focusing. The LA-EA1 and LA-EA2 (both discontinued, but still widely available at bargain prices) are designed for APS-C cameras like the a6000, while the LA-EA3 and LA-EA4 are intended for both APS-C and full-frame models like the A7-series. Table 9.1 should clear things up a bit.
The LA-EA2 adapter (or LA-EA4 if you plan to upgrade to full frame some day) is a much more satisfactory solution, but it costs a lot more, too. Both are shown in Figure 9.6. For some, either may be worth the price because they offer full-time phase detection autofocus, just like the Alpha’s SLT and dSLR siblings, with A-mount lenses, including useful optics like the 30mm f/2.8 macro lens and 18-200mm zoom shown in Figure 9.7. This miracle solution involves, basically, building a version of Sony’s Translucent Mirror Technology, found in the SLT cameras, into an adapter, as you can see in the exploded diagram shown in Figure 9.8. (In actual use, the lens must be physically mounted to the adapter.)
When I am out doing casual shooting, I carry my a6000 with a compact lens mounted (most often the 16-50mm kit lens or the 16mm f/2.8 with fisheye attachment). For more serious work, where weight is not a problem, I opt for the 16-70mm f/4 Zeiss lens, and often end up using my LA-EA4 adapter in tandem with one of my large collection of Minolta and Sony A-mount lenses. An amazing number of like-new optics in A-mount are available at steep discounts at keh.com, and I find myself there scavenging for lenses to add to my collection more often than I care to admit.
Figure 9.6 The LA-EA2 (left) and LA-EA4 (right) adapters allow using A-mount lenses on the a6000.
Figure 9.7 A-mount lenses like this 30mm macro lens (left) and 18-200mm zoom (right) can be used on the a6000 with an adapter.
Figure 9.8 The design of the LA-EA2 adapter looks like this.
If you’re not familiar with the SLT cameras, light from the lens reaches a semi-silvered non-moving mirror, with 70 percent continuing through the mirror and adapter to the a6000’s sensor. The 30 percent of the light reflected downward by the mirror is directed through a lens and another mirror to a 15-point AF sensor with three extra-sensitive cross-type sensors. The camera magically gains the same on-screen AF point selection options and high-speed phase detection autofocus in both Continuous AF and Single-shot modes as its SLT stablemates, and an electronic aperture drive mechanism allows full autoexposure functions with all A-mount lenses (except those used with a teleconverter). Virtually any Sony/Minolta A-mount lens can be used.
The seven-ounce, 3 1/8 × 3 1/2 × 1 3/4 inch LA-EA2 adapter is large, but it has a built-in tripod mount, so you can use it with large, heavy lenses that don’t have a tripod mount of their own. For $400 (plus the cost of your A-mount lenses), you can convert your a6000 mirrorless camera into a camera with a mirror! I’m glad Sony has made these accessories available for the a6000, but find it amusing that such a petite camera can be fitted with pounds and pounds of adapters, lenses, and viewfinders that transform it from a compact model to a model that’s easily the same size—or larger—than the SLT and dSLR alternatives.
WATCH THAT WEIGHT
Be aware than the a6000’s lens mount isn’t constructed to support the weight of very large lenses, such as the ones you might attach using either A-mount adapter. Support the lens by placing your hand under it (the tripod mount shown in the figure is a good choice), and if using the setup on a tripod or monopod, attach the device to the tripod mount on the adapter, and not to the a6000’s own tripod thread.
Because of the popularity of the camera line, third-party vendors have rushed to produce lenses for these models. You can find several Sigma DN and Carl Zeiss Touit lenses in the E-mount. Tamron makes their 18-200mm f/3.5-6.3 Di III VC lens in E-mount; this lens has the same f/stop range (with a small maximum aperture at long focal lengths) as Sony’s own 18-200mm optic. Naturally, Tamron uses its own proprietary image stabilizer called VC (for Vibration Compensation) and stepping motor autofocus mechanism that’s fast and quiet.
Because the a6000’s “flange to sensor” distance is relatively short, there’s room to use various types of adapters between camera and lens and still allow focusing all the way to infinity. There are already a huge number of adapters that allow mounting just about any lens you can think of on the a6000, if you’re willing to accept manual focus and, usually, a ring on the adapter that’s used to stop down the “adopted” lens to the aperture used to take the photo. You can find these from Novoflex (www.novoflex.com), Metabones (www.metabones.com), Fotodiox (www.fotodiox.com), Rainbow Imaging (www.rainbowimaging.biz), Cowboy Studio (www.cowboystudio.com), and others.
Some adapters of certain types and brands sell for as little as $20 to $30. Don’t expect autofocus even if you’re using an AF lens from some other system; as well, many of the cameras’ high-tech features do not operate. However, you can usually retain automatic exposure by setting the a6000 to Aperture Priority, stopping down to the f/stop you prefer, and firing away. Figure 9.9 shows a Nikon-to-E-Mount adapter I bought from Fotodiox.
Figure 9.9 It’s possible to mount lenses of entirely different brands on your a6000 with an adapter, but many camera functions are then disengaged.
The ultra-high grade Novoflex and Metabones adapters for using lenses of other brands sell for much higher prices. I found only two that are said to maintain autofocus with a lens of an entirely different brand. The Metabones Canon EF-to-Sony Smart Adapter (Mark III) and their similar Speed Booster model ($400 and $600, respectively) maintain autofocus, autoexposure, and the Canon lens’s image stabilizer feature when used with a camera. However, Metabones indicates that autofocus is “very slow and inadequate for most moving subjects.” The “Speed Booster” part of the name comes from the adapter’s ability to magically add one f/stop to the maximum aperture of the lens (thanks to the adapter’s internal optics), transforming an f/4 lens into an f/2.8 speed demon.
My absolute favorite lens bargain is the 35mm f/1.7 Fujian (no relation to Fuji) optic, which I purchased brand new for a total of $38, with the E-mount adapter included in the price. It’s actually a tiny CCTV (closed-circuit television) lens in C-mount (a type of lens mount used for cine cameras). It’s manual focus and manual f/stop, of course (and it works in Aperture Priority mode); it’s a toy lens, or something like a super-cheap Lensbaby (described next), or a great experimental lens for fooling around. It covers the full APS-C frame (more or less; expect a bit of vignetting in the corners at some f/stops), is not incredibly sharp wide open, and exhibits a weird kind of “bokeh” (out-of-focus rendition of highlights) that produces fantasy-like images. The only drawback (or additional drawback, if you will), is that you may have to hunt some to find one; the manufacturer doesn’t sell directly in the USA. I located mine on Amazon.com.
Once you own the C-mount to E-mount adapter, you can use any of the host of other similar CCTV lenses on your a6000. Also relatively cheap, but not necessarily of equal quality, are a 25mm f/1.4, 35mm f/1.7, and 50mm f/1.4 (shown in Figure 9.10), as well as a Tamron 8mm f/1.4, and other lenses that I haven’t tried and probably won’t cover the APS-C image area, but are worth borrowing to try out if you have a friend who does CCTV.
Figure 9.10 These CCTV lenses make great “toys” for your a6000.
The current products from Lensbaby include several models, including the Composer Pro with Sweet 35 shown in Figure 9.11. Most of these use glass elements mounted on a system that allows you to bend, twist, and distort the lens’s alignment to produce transmogrified images unlike anything else you’ve ever seen. Like the legendary cheap-o Diana and Holga cameras, the pictures are prized expressly because of their plastic image quality. It’s interesting to note that Jack and Meg White of the White Stripes are, in fact, selling personalized Diana and Holga cameras on their website for wacky lomography (named after the Lomo, another low-quality/high-concept camera). The various Lensbaby models are for more serious photographers, if you can say that about anyone who yearns to take pictures that look like they were shot through a glob of corn syrup.
Lensbaby optics are capable of creating all sorts of special effects. You use a Lensbaby by shifting the front mount to move the lens’s sweet spot (area that will be in focus) to a particular point in the scene. This is basically a selective focus lens that gets very soft outside the sweet spot. Most of the Lensbaby lenses are available in Sony E-mount; for the others, you can buy one of the inexpensive adapters discussed earlier. Do note however that there is no electronic communication between the camera and a Lensbaby even if it has the E-mount; follow the instructions to learn how to get good exposures if using one on your a6000.
The latest Lensbaby models, like the Composer Pro with Double Glass Optic, have the same shifting, tilting lens configuration as previous editions, but are designed for easier and more precise distorting movements. Hold the camera with your finger gripping the knobs as you bend the camera to move the central “sweet spot” (sharp area) to any portion of your image. With two (count ‘em) multicoated optical glass lens elements, you’ll get a blurry image, but the amount of distortion is under your control. F/stops from f/2 to f/22 are available to increase/decrease depth-of-field and allow you to adjust exposure. The lens focuses down to 12 inches and is strictly manual focus/manual exposure in operation. Most of the Lensbaby optics are not cheap, but there is really no other easy way to achieve the kind of effects you can achieve with one of their lenses.
Figure 9.11 Lensbaby Composer Pro with Sweet 35.
Figure 9.12 is an example of the type of effect you can get, in a photograph crafted by Cleveland photographer Nancy Balluck. She also produced the back cover photography of yours truly, and one of her specialties is Lensbaby effects. Nancy regularly gives demonstrations and classes on the use of these optics, and you can follow her work at www.nancyballuckphotography.com.
Here’s a quick look at the most popular Lensbaby models that were current as I wrote this; check out their website (www.lensbaby.com) for additional specifics.
Figure 9.12 Everything is uniquely blurry outside the Lensbaby’s “sweet spot,” but with the versatile models, you can move that spot around within your frame at will. This capability can be used for unusual selective focus effects, and it can simulate the dreamy look of some old-style cameras.
You can also get various accessories from Lensbaby, such as Macro Converters, a Super Wide converter, a Soft Focus Aperture Kit, and a Creative Aperture Kit with various shaped cutouts that can be used in place of the regular aperture insert that controls depth-of-field. There’s also an Optic Swap System kit with various adapters that include a pinhole lens, plastic lens, and single glass lens.
A sane approach to expanding your lens collection is to consider what each of your options can do for you and then choose the type of lens that will really boost your creative opportunities. Here’s a general guide to the sort of capabilities you can gain by adding a lens (using an adapter, if necessary) to your repertoire.
If you own one of the A-mount to E-mount adapters, you could use the DT 11-18mm f/4.5-5.6 ultra-wide zoom or the 16mm f/2.8 Fisheye lens from the larger SLT camera system. If you own only the LA-EA1 adapter, you’ll have only manual focus with these specific lenses. (Only SAM and SSM lenses will autofocus with this adapter.) Manual focus is fine with very short focal length lenses; they provide such prodigious depth-of-field that exact focus is not critical, except when shooting up close (less than six feet from your subject).
Figure 9.13 The 16mm f/2.8 lens with the VCL-ECU1 accessory provided this view of a castle in Prague.
Figure 9.14 This photo, taken from roughly the same distance, shows the view using a short telephoto lens.
Figure 9.15 A long (500mm) telephoto lens captured this view from approximately the same shooting position.
The need to manually focus an A-mount macro lens when used with the cheaper LA-EA1 adapter is not a tremendous hardship. Most serious photographers use manual focus in extreme close-up photography for the most convenient method of controlling the exact subject element that will be in sharpest focus. (The A-mount 30mm f/2.8 macro does autofocus with the adapter, but AF is so slow, I’ll use manual focus anyway.) As hinted earlier in this chapter, the A-mount 100mm f/2.8 macro lens ($800) is preferable to the shorter macro lenses in nature photography because you do not need to move extremely close to a skittish subject for high magnification. And you can get a frame filling photo of a tiny blossom without trampling all the other plants in its vicinity.
That makes the E-mount lenses with a very wide aperture (small f/number) such as the 24mm f/1.8 optic a prime choice (so to speak) for low light photography when you can get close to the action; that’s often possible at an amateur basketball or volleyball game. But, you might be happier with an adapter and an A-mount lens, such as the Carl Zeiss Sonnar T* 135mm f/1.8 lens (if money is no object; it costs $1,800). But there are lower cost fast lens options, such as the 50mm f/1.8 lens ($350), which might be suitable for indoor sports in a gym and whenever you must shoot in dark locations, in a castle or cathedral or theater, for example.
Lenses can be categorized by their intended purpose—general photography, macro photography, and so forth—or by their focal length. The range of available focal lengths is usually divided into three main groups: wide-angle, normal, and telephoto. Prime lenses fall neatly into one of these classifications. Zooms can overlap designations, with a significant number falling into the catchall wide-to-telephoto zoom range. This section provides more information about focal length ranges, and how they are used.
Any lens with an equivalent focal length of 10mm to 20mm is said to be an ultra-wide-angle lens; from about 20mm to 40mm (equivalent) is said to be a wide-angle lens. Normal lenses have a focal length roughly equivalent to the diagonal of the film or sensor, in millimeters, and so fall into the range of about 45mm to 60mm on a full-frame camera; with your a6000, a 30mm or 35mm lens is considered normal. Telephoto lenses usually fall into the 75mm and longer focal lengths, while those with a focal length much beyond 300mm are referred to as super telephotos.
To use wide-angle prime lenses and wide zooms, you need to understand how they affect your photography. Here’s a quick summary of the things you need to know.
You’ll find a wide-angle lens helpful when you want to maximize the range of acceptable sharpness in a landscape for example. On the other hand, it’s very difficult to isolate your subject (against a blurred background) using selective focus unless you move extremely close. Telephoto lenses are better for this purpose and as a bonus, they also include fewer extraneous elements of the scene because of their narrower field of view.
Figure 9.16 Tilting the camera produces this “falling back” look in architectural photos.
The depth-of-field advantage of wide-angle lenses disappears when you enlarge your picture. Believe it or not, a wide-angle image enlarged and cropped to provide the same subject size as a telephoto shot will have the same depth-of-field. Try it: take a wide-angle photo of a friend from a fair distance. Then, use a longer (telephoto) zoom setting from the same shooting position to take the same picture; naturally, your friend will appear to be larger in the second because of the greater telephoto magnification.
Download the two photos to your computer. While viewing the wide-angle shot, magnify it with the zoom or magnify tool so your friend is as large as in the telephoto image. You’ll find that the wide-angle photo will have the same depth-of-field as the telephoto image; for example, the background will be equally blurred.
Wide-angle lenses have a few quirks that you’ll want to keep in mind when shooting so you can avoid falling into some common traps. Here’s a checklist of tips for avoiding common problems:
Better quality lenses reduce both types of imaging defect; it’s common for reviews to point out these failings, so you can choose the best performing lenses that your budget allows. The Lens Comp.: Chro. Aber. Feature in the Custom Settings 5 menu, described in Chapter 3, can help reduce this problem. Leave it set for Auto to get the chromatic aberration reduction processing that the a6000 can provide.
Manufacturers like Sony do their best to minimize or eliminate it (producing a rectilinear lens), often using aspherical lens elements (which are not cross-sections of a sphere). You can also minimize barrel distortion simply by framing your photo with some extra space all around, so the edges where the bowing outward is most obvious can be cropped out of the picture. The Lens Comp.: Distortion feature, also described in Chapter 3, can help reduce this problem. Leave it set to Auto to allow the processor to minimize the slight barrel distortion that can occur with the more affordable lenses.
Figure 9.17 Many wide-angle lenses cause lines to bow outward toward the edges of the image. That’s often not noticeable unless you use a fisheye lens; the effect is considered to be interesting and desirable.
Think about it: if you use the 10mm end of the 10-18mm zoom, and point it at a part of a scene that’s at a the proper 90-degree angle from the sun, the areas of the scene that are at the edges of the frame will be oriented at 135 to 41 degrees from the sun. Only the center of the image area will be at exactly 90 degrees. When the filter is used to darken a blue sky, the sky will be very dark near the center of your photo. Naturally, the polarizing effect will be much milder at the edges so the sky in those areas will be much lighter in tone (less polarized). The solution is to avoid using a polarizing filter in situations where you’ll be including the sky with lenses that have an actual focal length of less than 18mm (or 28mm equivalent).
Telephoto lenses also can have a dramatic effect on your photography, but for now, the longest available focal length in E-mount is 200mm. Of course, A-mount lenses can be used with an adapter on your a6000 and Sony offers many telephotos to enhance your photography in several different ways. Here are the most important things you need to know. In the next section, I’ll concentrate on telephoto considerations that can be problematic—and how to avoid those problems.
Figure 9.18 A 300mm focal length and a wide aperture (small f/number) helped isolate this owl from its background.
Many of the “problems” that telephoto lenses pose are really just challenges and not that difficult to overcome. Here is a list of the seven most common picture maladies and suggested solutions.
If you do not have a powerful flash unit and cannot get closer to the subject (like Lady Gaga strutting her stuff on a dark stage), try setting the camera’s ISO level to 3200. This increases the sensitivity of the sensor so less light is required to make a bright photo; of course, the photo is likely to be grainy because of digital noise. If that does not solve the problem, you will need to set an even higher ISO, but then you’ll get even more obvious digital noise in your photo.
The term bokeh describes the aesthetic qualities of the out-of-focus parts of an image and whether out-of-focus points of light (circles of confusion) are rendered as distracting fuzzy discs or smoothly fade into the background. Boke is a Japanese word for “blur,” and the h was added to keep English speakers from rendering it monosyllabically to rhyme with broke. Although bokeh is visible in blurry portions of any image, it’s of particular concern with telephoto lenses. That’s because the magic of shallow depth-of-field produces more obviously defocused areas in photos made at long focal lengths.
Bokeh can vary from lens to lens, or even within a given lens depending on the aperture (f/stop) that you use. Bokeh becomes objectionable when the circles of confusion are evenly illuminated, making them stand out as distinct discs, or, worse, when these circles are darker in the center, producing an ugly “doughnut” effect. A lens defect called spherical aberration may produce out-of-focus discs that are brighter on the edges and darker in the center. You get this effect because the lens doesn’t focus light passing through the edges of the lens exactly as it does light going through the center. (Mirror or catadioptric lenses also produce this effect.)
Other kinds of spherical aberration generate circles of confusion that are brightest in the center and fade out at the edges, producing a smooth blending effect, as you can see at right in Figure 9.19. Ironically, when no spherical aberration is present at all, the discs are a uniform shade; this is better than the doughnut effect, but it’s not as pleasing as the bright center/dark edge rendition. The shape of the disc also comes into play, with round smooth circles considered the best, and nonagonal or some other polygon (determined by the shape of the lens diaphragm) considered less desirable. Most Sony lenses have near-circular irises, producing very pleasing bokeh at many apertures.
If you plan to use selective focus a lot, you should investigate the bokeh characteristics of a particular lens before you buy. Sony user groups and forums will usually be full of comments and questions about bokeh, so the research is fairly easy.
Figure 9.19 Bokeh is less pleasing when the discs are prominent (left), and less obtrusive when they blend into the background (right).
In Chapter 3, I introduced you to the a6000’s AF Micro Adjustment feature in the Custom Settings 5 menu, which can be manipulated only when you’re using a Sony or a Minolta Maxxum/Dynax A-mount lens with the LA-EA2 adapter and the newer LA-EA4 accessory. It is not available when using the LA-EA1 or LA-EA3 adapters. (The micro adjustment may work with an A-mount lens of another brand, but Sony warns that the results may be inaccurate.) Millions of A-mount lenses have been sold over the years, and the adapter is not terribly expensive, so I will assume that many readers will eventually want to consider the fine-tuning feature.
If you do not currently have such lenses or the adapter, you cannot use AF Micro Adjustment (you can turn the feature on or off, but you cannot enter any adjustment factor). But if you do own the relevant equipment, you might find that a particular lens is not focusing properly. If the lens happens to focus a bit ahead or a bit behind the desired area (like the eyes in a portrait), and if it does that consistently, you can use the adjustment feature.
Why is the focus “off” for some lenses in the first place? There are lots of factors, including the age of the lens (an older lens may focus slightly differently), temperature effects on certain types of glass, humidity, and tolerances built into a lens’s design that all add up to a slight misadjustment, even though the components themselves are, strictly speaking, within specs. A very slight variation in your lens’s mount can cause focus to vary slightly. With any luck (if you can call it that) a lens that doesn’t focus exactly right will at least be consistent. If a lens always focuses a bit behind the subject, the symptom is back focus. If it focuses in front of the subject, it’s called front focus.
You’re almost always better off sending such a lens in to Sony to have them make it right. But that’s not always possible. Perhaps you need your lens recalibrated right now, or you purchased a used lens that is long out of warranty. If you want to do it yourself, the first thing to do is determine whether or not your lens has a back focus or front focus problem.
For a quick-and-dirty diagnosis (not a calibration; you’ll use a different target for that), lay down a piece of graph paper on a flat surface, and place an object on the line at the middle, which will represent the point of focus (we hope). Then, shoot the target at an angle using your lens’s widest aperture (smallest available f/number) and the autofocus mode you want to test. Mount the camera on a tripod so you can get accurate, repeatable results.
If your camera/lens combination doesn’t suffer from front or back focus, the point of sharpest focus will be the center line of the chart, as you can see in Figure 9.20. If you do have a problem, one of the other lines will be sharply focused instead. Should you discover that your lens consistently front focuses or back focuses, it needs to be recalibrated. Unfortunately, it’s only possible to calibrate a lens for a single focusing distance. So, if you use a particular lens (such as a macro lens) for close-focusing, calibrate for that. If you use a lens primarily for middle distances, calibrate for that. Close-to-middle distances are most likely to cause focus problems, anyway, because as you get closer to infinity, small changes in focus are less likely to have an effect.
Figure 9.20 Correct focus (top), front focus (middle), and back focus (bottom).
The AF Micro Adj setting in the Custom Settings 5 menu is the key tool you can use to fine-tune your A-mount lens used with the adapter. Of course, this assumes you are using an A-mount lens and the adapter. You’ll find the process easier to understand if you first run through this quick overview of the menu options:
The first step is to capture a baseline image that represents how the lens you want to fine-tune autofocuses at a particular distance. You’ll often see advice for photographing a test chart with millimeter markings from an angle, and the suggestion that you autofocus on a particular point on the chart. Supposedly, the markings that actually are in focus will help you recalibrate your lens. The problem with this approach is that the information you get from photographing a test chart at an angle doesn’t actually tell you what to do to make a precise correction. So, your lens back focuses three millimeters behind the target area on the chart. So what? Does that mean you change the Saved Value by –3 clicks? Or –15 clicks? Angled targets are a “shortcut” that don’t save you time.
Instead, you’ll want to photograph a target that represents what you’re actually trying to achieve: a plane of focus locked in by your lens that represents the actual plane of focus of your subject. For that, you’ll need a flat target, mounted precisely perpendicular to the sensor plane of the camera. Then, you can take a photo, see if the plane of focus is correct, and if not, dial in a bit of fine-tuning in the AF Fine Tuning menu, and shoot again. Lather, rinse, and repeat until the target is sharply focused.
You can use the focus target shown in Figure 9.21, or you can use a chart of your own, as long as it has contrasty areas that will be easily seen by the autofocus system, and without very small details that are likely to confuse the AF. Download your own copy of my chart from www.dslrguides.com/FocusChart.pdf (the URL is case sensitive). Then print out a copy on the largest paper your printer can handle. (I don’t recommend just displaying the file on your monitor and focusing on that; it’s unlikely you’ll have the monitor screen lined up perfectly perpendicular to the camera sensor.) Then, follow these steps:
Figure 9.21 Use this focus test chart, or create one of your own.
If you’ve reached the maximum number of lenses (which is unlikely—who owns 30 lenses?), mount a lens you no longer want to compensate for, and reset its adjustment value to +/-0. Or you can reset the values of all your lenses using the Clear function and start over.
Many of the Sony lenses are equipped with the Optical SteadyShot (OSS) stabilizer that provides camera steadiness that’s the equivalent of at least two or three shutter speed increments. In other words, if you can get a sharp photo with a 55mm focal length using a shutter speed of 1/50th second when hand-holding it, you should be able to get an equally blur-free photo at about 1/13th second, or perhaps 1/10th second when OSS is active. (See the examples shown in Figure 9.22.) This extra margin can be invaluable when you’re shooting under dim lighting conditions or hand-holding a long lens. While visiting Prague, I found that I was often shooting inside beautiful old buildings where flash or a tripod were impractical or prohibited. The OSS stabilizer was often very useful. I’m sure you can think of similar situations where you’ll appreciate this feature.
However, keep these facts in mind:
Figure 9.22 When hand-holding a lens at a 55mm focal length (left) I was unable to get a blur-free photo at 1/13th sec. Activating the OSS provided a photo that’s sharp (right) except for slight blurring of the moving lady behind the bananas.
