The vast majority of your nature photography is probably accomplished with your core setup of camera and three-lens kit (wide-angle zoom, midrange zoom and tele-zoom). Using that gear, you take care of at least 90 percent of your shots. Every once in a while, though, you have a need for a more exotic lens—something special. But these out-of-the-ordinary lenses also tend to be very pricey pieces of gear, especially when you consider that you don’t use them all that often. It can be hard to justify the cost when you’ll only be using a super-telephoto, super-wide-angle or fisheye lens on rare occasions.
There’s a simple photo accessory that can give you access to these and other lenses for relatively little cost. It’s the lens adapter, and it lets you use lenses on your camera that you couldn’t use otherwise. A quick visit to eBay.com or Amazon.com or the like will reveal a wide variety of used, older lenses that are reasonably priced, but may not fit your new, high-tech AF DSLR. An inexpensive lens adapter or two will let you use these lenses on your camera.
The recent proliferation of video-capable DSLRs has expanded the nature photographer’s horizons tremendously. But the contrast-based AF systems these cameras use for video work is very slow, so it’s generally best to focus manually. The AF lenses for these cameras have focusing mechanisms that were designed for autofocusing, not smooth and easy manual focusing. And some such DSLRs won’t let you set apertures manually during video recording. An adapter will let you attach an older manual-focus lens with an aperture ring and a focusing system designed for manual operation, so you can easily set everything as desired.
Adapters also let you use favorite lenses from your previous SLR system with a new DSLR that has a different mount. And they let you use optics that may not be available in mounts for your camera, like mirror lenses. Some aficionados of respected Leica and Zeiss lenses use adapters to mount these on other brands of cameras.
And adapters don’t just let you use old lenses on new cameras. They can also expand the range of lenses available for brand-new cameras. When the Micro Four Thirds System was introduced a couple of years ago, there were few Micro Four Thirds System lenses available. But simple adapters made it possible to supplement these with the full range of standard Four Thirds System lenses (even retaining autofocusing capability with many of them).
When Sony announced their new NEX-3 and NEX-5 mirrorless interchangeable-lens models (which, despite their tiny size, contain DSLR-sized APS-C image sensors), they also announced the Alpha NEX Camera Mount Adapter, which allows NEX-3 and NEX-5 users to attach the full range of lenses for Sony’s Alpha DSLRs to their cameras, instantly expanding the NEX camera user’s focal-length options.
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You don’t get something for nothing, though, and in the case of lens adapters, there are some trade-offs of which to be aware. Here are some things to consider when choosing an adapter.
Can I Use This Lens On This Camera?
Whether you can use a given lens on a given camera body depends on several things. First, an appropriate adapter must be available. Second, the flange back distance must be compatible. Third, the lens must not physically interfere with the DSLR’s mirror, which swings up and down. Fourth, the lens should cover the camera format.
Adapters are available to mount a wide range of lenses on a wide range of bodies. See the Resources box for some sources (or do a web search for “A to B adapter,” where A is your camera body and B is the lens you wish to use with it).
The flange back distance is the distance between the lens mount and the image plane. If the lens was designed for a shorter distance than that of the camera body, the lens won’t focus out to infinity (although you can use it for close-up photography). There are adapters that contain glass elements to allow such lenses to focus out to infinity, but these also act as low-power teleconverters (they increase the focal length somewhat and reduce the effective aperture a bit), and the added elements can reduce sharpness and contrast. If the adapter isn’t thick enough, the flange back distance will be too short and the lens will focus beyond infinity. Since adapters—especially the lower-priced ones—tend to vary in precision, it’s a good idea to buy yours from a source that will allow you to return it if it doesn’t provide proper focusing.
Some lenses have designs that protrude into the camera body, either at all times or during focusing. These lenses shouldn’t be used on cameras where they’ll strike the DSLR mirror. It’s possible, with some cameras, to use such lenses with the mirror locked up, but you can’t see through the DSLR’s optical viewfinder with the mirror locked up to compose and focus, and you can damage the camera and lens should the mirror come back down with the lens attached, so it’s best to avoid such lens/camera combinations.
The new mirrorless interchangeable-lens cameras (Olympus PEN E-P1, E-PL1 and E-P2, Panasonic Lumix DMC-G2, G10, GF1 and GH1, Samsung NX10 and Sony Alpha NEX-3 and NEX-5) don’t contain SLR mirror boxes and thus have a very short flange back distance, so they can accept pretty much any lens for which an adapter can be found, and the lens-and-lens-adapter combination will be able to focus out to infinity.
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When using a lens adapter, also keep in mind the format for which the lens was designed. Lenses designed for Four Thirds System DSLRs, for example, would vignette on APS-C or full-frame DSLRs, or 35mm SLRs, because their 21.63mm image-circle diameter is too small to cover the larger image formats. For the most part, adapters aren’t available to attach smaller-format lenses to larger-format cameras, so this shouldn’t be a big problem.
Another consideration is electronic linkage. Canon EF lenses use electronic diaphragms, so you can’t change the aperture when an adapter ring disconnects the electronic linkage between lens and camera. This—and the EOS system’s flange back distance, which is slightly shorter than that of other DSLRs—is why you don’t see adapters to connect EOS lenses to other DSLRs.
All of these things make it a good idea to consult the adapter maker’s specs (or query the manufacturer/distributor) to make sure the adapter will work with the lens-and-camera combo you want to use.
How To Achieve Critical Focus With An Adapter
The focusing screens in AF SLRs were designed for autofocusing, not for manual focusing. The focusing screens in manual-focus DSLRs have focusing aids such as central split images and microprism collars on ground-glass focusing screens that make it easier to focus manually. Some hard-core lens-adapter fans will change to one of these screens if their AF DSLR accepts interchangeable focusing screens and such a screen is available for it. A better solution, if your DSLR offers Live View, is to focus manually using the magnified Live-View image.
Some adapters come with chips that activate an AF DSLR’s focus-assist system so the “in-focus” lamp in the viewfinder glows when you’ve achieved focus manually. You also can buy chips and install them on the adapters yourself. Some adapters from Novoflex incorporate an aperture-control ring so you can adjust apertures with lenses that lack one, such as Nikon’s G-series. With most adapters, you can use manual exposure control or aperture-priority AE, but focusing will be manual (an exception is adapters to attach autofocus Four Thirds System lenses to Micro Four Thirds System cameras—some adapters retain autofocusing capability with some of these lenses).
When you use a compatible lens, a modern DSLR will keep the aperture wide open for easy composing and focusing, regardless of the aperture you choose for the shot. The camera then will automatically stop down the lens to the selected aperture when you depress the shutter button to make the shot.
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There are adapters for attaching all sorts of lenses to all sorts of bodies. You lose some camera functions, but these setups are really for rare shooting situations. The Adorama adapter also gives you some tilt and shift capability (above).
This automatic diaphragm operation doesn’t work when you use a lens adapter because the adapter doesn’t provide the necessary linkage. So you have to use stopped-down metering: You open the lens to its maximum aperture to get a bright image for focusing and composing, then manually stop it down to the aperture desired for the shot, and the camera meters at that aperture. Stopped-down metering isn’t always accurate, and some lenses shift focus when the aperture is changed—two things to keep in mind when using such adapters. DSLR users can refer to the histogram and LCD monitor image to check exposures.
There are a number of companies offering lens adapters under various brand names. The accompanying Resources box provides more sources. However, there are some major players in the adapter market. Here’s a quick rundown.
Adorama offers a wide range of adapters, including their Flashpoint Tilt Adapter for Nikon Lens to Micro 4/3. Besides allowing you to mount Nikon lenses on Micro Four Thirds System cameras, this adapter allows you to tilt the lens 12° in any direction thanks to 360° rotation capability.
CameraQuest distributes an extensive range of adapters to mate a wide number of SLR and DSLR bodies with a wide range of lenses. Their website includes lots of good adapter information.
Novoflex also offers a wide range of adapters, including some to fit popular SLR lenses to Samsung’s new NX10 mirrorless camera.
Four Thirds System pioneer Olympus offers adapters to use Four Thirds System lenses on Micro Four Thirds System cameras, and old manual-focus Olympus Zuiko OM-system lenses on both Four Thirds and Micro Four Thirds System cameras. With Four Thirds System lenses that are compatible with contrast-based autofocusing, AF capability is retained.
Micro Four Thirds System pioneer Panasonic offers adapters to mount Four Thirds System and Lecia M- and R-mount lenses on Micro Four Thirds System cameras, while retaining most, if not all, camera features.
Sony provides an adapter to mount Sony Alpha-mount DSLR lenses (and legacy Minolta Maxxum lenses) on its new Alpha NEX-3 and NEX-5 mirrorless cameras.
Zoerk offers adapters to mount medium-format lenses on 35mm and DSLR bodies, as well as adapters that provide shift and tilt capability with enlarger lenses on film and DSLRs.
|Lens Mount 101: Why So Many?
If you’ve been using an interchangeable-lens camera for a while, you’ve probably mused, “Wouldn’t it be nice if all cameras and lenses used the same mount, so any lens could be used on any camera?” As you’ve seen in the section “Can I Use This Lens On This Camera?” that’s not the case, for the reasons explained. But why are there so many different lens mounts?
Basically, it’s because each camera manufacturer designs a mount it feels is optimal for its cameras. Lens makers (including the camera manufacturer) then have to make lenses to work with that mount. For example, when Canon went autofocus in 1987, they developed the all-electronic EF mount, which offered a number of advantages but meant that previous Canon SLR lenses couldn’t be used on the EOS cameras. Nikon, conversely, adapted its F mount for autofocus use, so that longtime Nikon users could use their lenses with the new AF cameras (albeit with manual focusing).
In 2003, Olympus introduced the Four Thirds System, with an entirely new lens mount, designed specifically for a new 17.3×13.0mm Four Thirds System digital image sensor, rather than adapting existing 35mm SLR bodies to digital use as other manufacturers had done. Four Thirds is an open system, so any Four Thirds System lens can be used on any Four Thirds System camera, regardless of manufacturer. The new Micro Four Thirds System created an even smaller mount (although it uses the same-size Four Thirds System image sensor), made possible in part by eliminating the SLR’s mirror box. Micro Four Thirds is also an open system, so all Micro Four Thirds lenses can be used on all Micro Four Thirds cameras (but not on regular Four Thirds System cameras because the lenses’ flange back distance is too short and the lens-mount diameter is 6mm smaller). Regular Four Thirds System lenses can be used on Micro Four Thirds bodies, via adapters.
When Sony purchased Konica Minolta’s SLR technology a few years back, they retained the Maxxum lens mount, and all Sony DSLRs can use Maxxum lenses, as well as Sony A-mount lenses. When Sony recently introduced its mirrorless NEX-3 and NEX-5 cameras, which wrap SLR-sized APS-C image sensors in truly tiny bodies, they also introduced an adapter that permits using the Maxxum/Sony SLR lenses on the mirrorless cameras. The adapter retains auto aperture control, and incorporates a tripod mount—important, since most Sony SLR lenses are much heavier than the tiny camera bodies.
There have been attempts at “universal” lens systems. The M42 screw mount (widely known as the “Pentax universal screw mount,” although Zeiss actually introduced it) appeared on a number of 35mm cameras from a number of manufacturers over the years, and there are so many M42-mount lenses out there that adapters are available to attach them to almost any SLR. Tamron’s T-mount enabled the company to produce one version of each lens and attach it to a variety of SLRs via T-mount adapters. But ultimately, the convenience (and optical performance) of integrated lens mounts prevailed, and today Tamron, like Sigma and Tokina, produces each lens it offers in a variety of mounts for popular film and digital SLRs.
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