SOME PHOTOGRAPHERS still ask if they can use old 35mm-film lenses on new DSLRs. The answer is yes you can, but you probably won’t want to. Why? Because digital sensors handle light differently than film. Designed-for-digital lenses focus light differently to better register on the image sensor, and digital-specific coatings maximize color and sharpness. Plus, newer lenses often are sharper than old ones—and that’s increasingly important with high-res sensors.
Choosing the perfect lens means more than just buying the newest models, though. Fit a lens to your personal style and the things you photograph most often, as well as the features and budget that meet your needs. You don’t have to buy the most expensive glass to make the best lens choice. You just have to understand which features will provide what you’re looking for.
LENS FUNDAMENTALS
The focal length of a lens is the first thing most photographers look at when considering a lens. It’s the most apt broad definition of what a lens does—and that’s providing a field of view that’s normal, wide or telephoto. Normal lenses approximate the human eye, somewhere in the 40-60mm range. Wide-angles are shorter than 40mm (and most often somewhere in the 20s), while telephotos are 70mm or longer.
Wide-angle lenses are great for cramped spaces or to make landscapes look even more vast. Short telephotos (in the 80-150mm area) are great portrait lenses, while longer glass (200mm, 300mm, 600mm, even 800mm) is ideal for getting close-ups of small and distant subjects, like sports and wildlife. Telephotos compress a scene greatly in the opposite way that wide-angles expand a view.
All of these measurements are given in 35mm-film-equivalent terms. When working with sensors smaller than full frame, focal lengths will behave proportionally longer. Some lenses are designed exclusively for small APS or Four Thirds formats and will work only with those particular cameras. To make comparing lenses easier, though, manufacturers often refer to focal lengths in standard 35mm-equivalent terms.
If a lens is a fixed focal length—35mm, 50mm or 100mm, for instance—it’s known as a prime lens. If a lens covers a range of focal lengths, like 28-70mm, it’s a zoom. Choosing primes or zooms is largely a matter of personal preference. Would you like one lens that covers the range of three primes in order to travel light or work quickly? If you want one lens to do it all, an extreme zoom that covers everything from wide-angle to telephoto could be perfect. Or if you want a handful of lenses that are fast and do one thing really well, consider purchasing primes.
Some lenses are designed to do very specific things. Macro lenses, for instance, focus very close, enabling photographers to greatly magnify tiny subjects beyond life-size. Macro lenses often are 50mm and 100mm primes, but many zooms also have moderate macro capabilities, too.
Fisheye lenses are extreme wide-angles (often with focal measurements in the teens) that deliver an angle of view greater than 100° and often as much as 180º. Not all superwides are fisheyes, but all fisheyes are superwide. Some fisheye lenses actually create a circular image in the center of the frame, making it possible to create circular, full-sky images.
LENS SPEED
Lenses control how much light passes through by way of an aperture. Every lens has a range of these ƒ-stops, from maximum (as wide open as the lens can be, corresponding to a small number like ƒ/2) to minimum (as stopped down as a lens can close, with a large number like ƒ/32).
The maximum aperture, known as the “speed” of a lens, is critical. Working in low-light situations in which a fast shutter speed is needed (stopping sports action, for instance), a larger maximum aperture is worth its weight in gold. Fast lenses—say, ƒ/2 or even ƒ/1.4—are more expensive than slower lenses because they’re more versatile. They’re also often larger because they require bigger elements. Consequently, many lens makers incorporate variable maximum apertures in their zoom lenses, from ƒ/3.5 at the wide end to ƒ/5.6 at the telephoto end, for instance. A variable-maximum-aperture zoom is usually lighter and less expensive than a fixed-aperture model.
DECIPHERING THE CODES
When shopping for lenses, you’re bound to notice a variety of acronyms and cryptic codes appended to lens names. Codes like SD, ED and T* refer to optical characteristics and coatings that are designed to deliver better color, contrast and sharpness. Coatings on internal elements minimize lens flare, while front-element coatings make glass scratch- and dust-resistant.
If you see codes like IS, OS and VR, you’re looking at a lens with image stabilization. The manufacturers’ terms are different, but the functions are the same—to reduce the effects of camera shake for sharper images when handholding, sometimes by as much as two full stops of steadying power (so instead of seeing camera shake at 1/60 sec., you can hold steady even at 1/15 sec.). Everything comes with a price, though, and stabilization is often paid for in the heft and cost of a lens.
HSM and USM refer to autofocus motors. The hypersonic and ultrasonic designations are designed to be, clearly, really fast. If focusing speed is critical, say, for sports or fast-moving wildlife, look to these lenses.The term ASPH is short for aspherical. Instead of a wide-angle image focused correctly in the center and distorted at the edges, aspherical elements help keep sharpness constant. Wide-angle lenses tend to distort straight lines into curves, and for that, rectilinear designs intervene to keep straight lines straight, as well.
Fisheye lenses are extreme wide-angles (often with focal measurements in the teens) that deliver an angle of view greater than 100° and often as much as 180º. Not all superwides are fisheyes, but all fisheyes are superwide. Some fisheye lenses actually create a circular image in the center of the frame, making it possible to create circular, full-sky images.
LENS SPEED
Lenses control how much light passes through by way of an aperture. Every lens has a range of these ƒ-stops, from maximum (as wide open as the lens can be, corresponding to a small number like ƒ/2) to minimum (as stopped down as a lens can close, with a large number like ƒ/32).
The maximum aperture, known as the “speed” of a lens, is critical. Working in low-light situations in which a fast shutter speed is needed (stopping sports action, for instance), a larger maximum aperture is worth its weight in gold. Fast lenses—say, ƒ/2 or even ƒ/1.4—are more expensive than slower lenses because they’re more versatile. They’re also often larger because they require bigger elements. Consequently, many lens makers incorporate variable maximum apertures in their zoom lenses, from ƒ/3.5 at the wide end to ƒ/5.6 at the telephoto end, for instance. A variable-maximum-aperture zoom is usually lighter and less expensive than a fixed-aperture model.
DECIPHERING THE CODES
When shopping for lenses, you’re bound to notice a variety of acronyms and cryptic codes appended to lens names. Codes like SD, ED and T* refer to optical characteristics and coatings that are designed to deliver better color, contrast and sharpness. Coatings on internal elements minimize lens flare, while front-element coatings make glass scratch- and dust-resistant.
If you see codes like IS, OS and VR, you’re looking at a lens with image stabilization. The manufacturers’ terms are different, but the functions are the same—to reduce the effects of camera shake for sharper images when handholding, sometimes by as much as two full stops of steadying power (so instead of seeing camera shake at 1/60 sec., you can hold steady even at 1/15 sec.). Everything comes with a price, though, and stabilization is often paid for in the heft and cost of a lens.
HSM and USM refer to autofocus motors. The hypersonic and ultrasonic designations are designed to be, clearly, really fast. If focusing speed is critical, say, for sports or fast-moving wildlife, look to these lenses.The term ASPH is short for aspherical. Instead of a wide-angle image focused correctly in the center and distorted at the edges, aspherical elements help keep sharpness constant. Wide-angle lenses tend to distort straight lines into curves, and for that, rectilinear designs intervene to keep straight lines straight, as well.
A NEW LENS FOR EVERY NEED
Since we can’t possibly cover all of the terrific lens options from each manufacturer, here are some new lenses worth noting to give you an idea of what’s available.
SUPERWIDE PRIME
At the shortest end of the spectrum are lenses that provide superwide angles of view great for landscape and interior photography. The Zeiss Distagon T* 3.5/18 prime is a high-quality manual-focus lens available for Pentax, Nikon and now Canon mounts. The ƒ/3.5 lens is compact and light, making it a great choice for those who value portability and performance. The CPU included in ZF.2 and ZE versions for Nikon’s F and Canon’s EF mounts also enable communication between lens and camera for controlling aperture and transferring lens data in the EXIF file. Estimated Street Price: $1,395.
Since we can’t possibly cover all of the terrific lens options from each manufacturer, here are some new lenses worth noting to give you an idea of what’s available.
SUPERWIDE PRIME
At the shortest end of the spectrum are lenses that provide superwide angles of view great for landscape and interior photography. The Zeiss Distagon T* 3.5/18 prime is a high-quality manual-focus lens available for Pentax, Nikon and now Canon mounts. The ƒ/3.5 lens is compact and light, making it a great choice for those who value portability and performance. The CPU included in ZF.2 and ZE versions for Nikon’s F and Canon’s EF mounts also enable communication between lens and camera for controlling aperture and transferring lens data in the EXIF file. Estimated Street Price: $1,395.
 |
For shooters who want a wide prime that’s not so extreme, consider the Pentax DA 15mm ED lens. How can a shorter lens have a narrower field of view? Because this ƒ/4 prime is made for smaller APS-C sensors—making it the equivalent of a 23mm lens. Machined from high-grade aluminum, this Pentax Limited Series lens fits the wide format prized by photojournalists for providing context in environmental portraits and documentary photography without perspective distortion. Estimated Street Price: $649.
 |
For a wide-angle lens with more built-in flexibility, consider a really wide zoom like Tokina’s newly announced AT-X 16-28mm PRO FX lens. The zoom is fast with a constant ƒ/2.8 maximum aperture, and on a full-frame camera, it’ll provide a superwide angle of view at the 16mm end. At the 28mm setting, the lens is ideal for Nikon and Canon shooters who want a wide view from a more “normal” perspective. List Price: $1,499.
 |
Sigma’s brand-new 17-50mm F2.8 EX DC OS HSM zoom offers a fast, constant ƒ/2.8 maximum aperture. The speed, compact size and variable wide-to-normal focal range make it an ideal lens for those who want to carry only a single versatile lens, and advanced optical stabilization offers up to four stops of added handholding stability. Available in Sigma, Sony, Nikon, Canon and Pentax mounts, the lens is less expensive than many equally fast full-frame zooms. Estimated Street Price: $669.
EXTREME SUPERZOOM
 |
 |
Sony Alpha shooters with a penchant for portraits will appreciate the long focal range of the 70-200mm G-series telephoto zoom. A really fast ƒ/2.8 maximum aperture remains constant, making it ideal for low-light shooting of action, as well. Smart features like focus-stop buttons on the barrel (which can be assigned to functions such as depth-of-field preview) improve usability. Built for full-frame cameras, the lens also can be used with the APS-C format on which it performs like a long 105-300mm telephoto.
Estimated Street Price: $1,799.
SUPER-TELE-ZOOM
Sports and wildlife photographers often seek out longer telephoto lenses, and the SP 70-300mm F/4-5.6 Di VC zoom from Tamron is usually what they’re looking for. Short enough at 70mm to be useful in a variety of situations, yet long enough at 300mm to create great close-ups, the versatile lens fills a frequently used telephoto range in a compact frame. The lens has built-in vibration compensation to help keep it steady when handholding—crucial for optimum sharpness when working with a long lens. The Ultrasonic Silent Drive motor ensures fast and quiet autofocusing. Available in Canon, Nikon and Sony mounts. Estimated Street Price: $449.
Sports and wildlife photographers often seek out longer telephoto lenses, and the SP 70-300mm F/4-5.6 Di VC zoom from Tamron is usually what they’re looking for. Short enough at 70mm to be useful in a variety of situations, yet long enough at 300mm to create great close-ups, the versatile lens fills a frequently used telephoto range in a compact frame. The lens has built-in vibration compensation to help keep it steady when handholding—crucial for optimum sharpness when working with a long lens. The Ultrasonic Silent Drive motor ensures fast and quiet autofocusing. Available in Canon, Nikon and Sony mounts. Estimated Street Price: $449.
 |
For pro photographers, speed is key. That’s why Nikon has added another superfast prime to its pro lineup. The brand-new AF-S Nikkor 85mm ƒ/1.4G is an internal focusing 85mm prime lens—perfect for portrait and wedding photographers or even nature photographers and photojournalists who value wide apertures. Nano Crystal Coat helps minimize internal flare, and the M/A mode switch on the barrel makes instantly changing to manual focus a snap. Blazing speed and high quality, however, don’t come cheap. Estimated Street Price: $1,649.
 |
Canon’s 100mm macros have long been a favorite of detail shooters who value their sharpness and ideal medium-telephoto focal length. The company’s newest version of the lens makes improvements with the addition of image stabilization for easier handholding—crucial when working with microscopic subjects mere millimeters from the lens. The new hybrid IS in the EF 100mm ƒ/2.8L Macro IS USM lens addresses the unique challenges of stabilizing lens optics at close focusing distances. Canon claims up to two stops of added stabilization at close focus and a whopping four stops of steadiness at longer distances. Estimated Street Price: $949.
No comments:
Post a Comment