Best mid-price telephoto lenses

How much should you pay?

A telephoto zoom is the first additional lens most DSLR or compact system camera owners go for. These can be pretty cheap but, unfortunately, the performance can be disappointing.

Cheap telephoto zooms tend to lose sharpness at their maximum zoom setting, which is where you most often want to use them.

Cheap telephotos also have a maximum aperture that shrinks as you increase the zoom. They might start out at f/4, for example, at their shortest zoom setting, but as you zoom in the maximum aperture typically shrinks to f/5.6 or even f/6.3.

To keep shutter speeds fairly fast for minimising camera-shake and motion blur, you can often find yourself having to combine the longest zoom setting with the widest aperture, which can really degrade image sharpness.

At the other end of the scale, fully professional telephoto zooms like the Canon EF 70-200mm f/2.8 L IS II USM, the Nikon AF-S 70-200mm f/2.8G ED VR II and the Sony 70-200mm f/2.8 G SSM II are much more refined. The relatively wide f/2.8 aperture remains available throughout the zoom range, and the physical dimensions of the lenses remain fixed at all zoom and focus settings.

But these professional lenses come with problems of their own. First, they're expensive – they can cost as much as some full-frame DSLRs. Second, they have large front lens elements to provide that f/2.8 aperture all the way through the zoom range, so they are big and heavy and typically weigh in at around 1.5kg.

But one popular compromise is to opt for a less expensive 70-200mm f/4 telephoto zoom. You lose one f-stop in maximum aperture but it's still constant throughout the zoom range. These lenses are smaller, lighter and cheaper – yet you can still expect robust build quality and premium-grade glass.

Wide maximum apertures aren't quite as important as they used to be. The latest DSLRs usually deliver excellent image quality at raised ISO settings, and you won't see much of a loss in quality if you raise the ISO setting by 1 stop to allow for an f/4 lens versus an f/2.8 lens. You can still get very shallow depth of field when shooting at 200mm at f/4, so it's still possible to get nicely defocused backgrounds.

Another bonus for Canon and Nikon shooters is that some of the latest DSLRs can autofocus when the widest available aperture is as small as f/8. This means you can fit a compatible 2x tele-converter to a 70-200mm f/4 lens without having to resort to manual focussing. Live View focussing is also possible at even narrower apertures but, on DSLRs at least, it tends to be very slow.

Third-party lenses

Another way to reduce purchase costs is to switch brands. Compared with 70-200mm f/2.8 lenses from the likes of Canon, Nikon and Sony, direct competitors from Sigma and Tamron can cost half the price or less. Even so, they still offer a very good standard of build quality, upmarket optical elements, and similar ring-type ultrasonic autofocus systems, as used on own-brand telephotos. The latter can be an important consideration, because many of us use this type of lens for sports, action and wildlife photography, where fast, accurate autofocus is vital.

The Panasonic Micro Four Thirds and Sony E-mount lenses are the only ones in this round-up to lack ring-type ultrasonic autofocus. Instead, they use stepping motors. (Canon DSLR users with the latest 18-55mm or 18-135mm STM kit lenses will be familiar with this technology.)

A plus point for video shooting is that this autofocus technology is practically silent, while also giving smooth focus transitions without the lurching effect of conventional systems. The downside is that, in DSLR lenses at least, autofocus isn't particularly quick. Our tests do reveal a slight performance deficit with the Panasonic and Sony lenses.

For hand-held telephoto shooting, image stabilization is another key factor. At long focal lengths, we've generally found that in-lens optical stabilization is more effective than camera-based, sensor-shift stabilization. Indeed, Canon and Nikon SLRs don't have in-camera stabilization at all.

What to look for

Prime concern

Zoom lenses aren't the only option. At any given price point, prime (fixed focal length) telephoto lenses often offer wider available apertures, a more compact build, and better overall image quality. The Pentax DA* 200mm is certainly one of the smaller lenses in this test group – and the least expensive, despite having a wide f/2.8 aperture.

By contrast, the Sigma APO 180mm prime is the heaviest and most expensive lens in the group. However, it's a dual-purpose telephoto and macro lens, delivering full 1.0x magnification at its shortest focus distance.

Sensor size and effective focal length

Getting back to the greater convenience and versatility of zoom lenses, 70-200mm is the most popular telephoto range, at least for constant-aperture designs. All five 70-200mm lenses featured in this round up are compatible with full-frame sensors. Being a Micro Four Thirds lens with a 2x focal-length multiplier (or crop factor), the Panasonic 35-100mm has the same effective range as the other zoom lenses when they're mounted on full-frame bodies.

However, when using 70-200mm lenses on cameras with APS-C sensors, you get a boost in effective reach. This is usually 1.5x for most APS-C format cameras, and 1.6x for Canon bodies, resulting in effective zoom ranges of 105-300mm or 112-320mm respectively.

Faster autofocus

All these test lenses have fully internal focus systems, which gives two advantages. First, the front element remains fixed throughout the whole focus travel. It neither rotates nor extends, making it easier to use rotation-specific filters like circular polarisers and ND grads.

Second, because focussing relies on the movement of relatively small inner or rear elements within the lens, autofocus speed tends to be rather faster. This can be a major bonus in sports and action photography, both for rapid acquisition of autofocus and for tracking moving targets in Continuous AF mode.

Features to look for

Prime vs zoom: For sports and wildlife shoots, zoom telephoto lenses do give greater versatility than primes, especially when you're limited to a specific viewing area or taking cover in a hide.

The long view: Constant-aperture 70-200mm lenses have a fairly long physical length of 175-200mm. but wiith internal zoom systems, their overall length stays fixed at any focal length.

Feel the width: For any given focal length, lenses with wider available apertures will have a bigger diameter front element, and a bigger filter size. For 70-200mm f/4 and f/2.8 lenses, it's typically 67mm or 77mm respectively.

Keep it quiet: For wildlife and bird photography, quiet autofocus can be a big help. Ring-type ultrasonic systems tend to be whisper-quiet, whereas stepping motor systems are virtually silent.

Optical stabilization: Nearly all of the lenses on test feature built-in optical stabilization. However, stabilization is omitted in the Pentax 200mm lens and the Sony A-mount edition of the Tamron 70-200mm because they camera's they're designed for have stabilization built into the body.

Included accessories: Every lens in the group comes complete with front and rear caps, carrying pouch and hood. A tripod collar and mounting foot is also supplied with the heavier lenses.

Eight top mid-price telephotos

Canon EF 70-200mm f/4L IS USM

• Canon EF 70-200mm f/4L IS USM review

Canon's 70-200mm is relatively slim but still has a constant f/4 maximum aperture. Like many of Canon's L-series (luxury) lenses, this one is finished in cream or off-white, rather than the usual black. The idea is that the outer surface reflects more light, and therefore incurs less heat build-up when used in bright sunlight for long periods of time.

Like most other Canon L-series lenses, it has a weather-sealed construction, which is lacking in the non-stabilized edition of the EF 70-200mm f/4L USM. It can be used on both full frame Canon DSLRs and APS-C format models (where the equivalent focal length is 112-320mm.

Nikon AF-S 70-200mm f/4G ED VR

• Nikon AF-S 70-200mm f/4G ED VR review

This Nikon 70-200mm f/4 only gives away 1 stop in maximum aperture to Nikon's legendary 70-200mm pro lens, but it's both lighter and cheaper. It can be used on full-frame (FX format) Nikons as well as APS-C (DX format) models, where the effective focal length is 105-300mm.

It's well made, with a weather-sealed mounting plate and a switch for AM/M focussing – the AM mode enables autofocus with full-time manual override. There's also a focus limiter, which locks out autofocus distances shorter than 3m, and two Vibration Reduction switches – on/off and normal/active. It has auto-detection for panning, and the active mode is designed for shooting from a vibrating platform.

Panasonic G X 35-100mm f/2.8 Power OIS

• Panasonic G X 35-100mm f/2.8 Power OIS review

This is a fast and powerful telephoto for Micro Four Thirds cameras. The fact that Micro Four Thirds sensors are slightly smaller than APS-C means that fast, constant aperture lenses like this are smaller and lighter than their DSLR equivalents.

The smaller sensor also gives this lens a longer reach – the effective focal range is actually 70-200mm, so it's a direct equivalent to the 70-200mm f/2.8 pro lenses on full-frame DSLRs. Build quality feels solid and includes dust and splash resistance, while the stepping motor autofocus system is typically silent.

Pentax DA* 200mm f/2.8 ED IF SDM

• Pentax DA* 200mm f/2.8 ED IF SDM review

Pentax's 200mm f/2.8 prime lens has pros and cons. Prime lenses aren't as flexible as zooms, obviously, but they do typically offer faster maximum apertures and should bring better image quality. Pentax only makes APS-C format cameras, so this effectively becomes a 300mm f/2.8 lens on a Pentax DSLR. It's slightly shorter than most 70-200mm f/4 zoom lenses, but roughly the same weight, despite being a full f-stop faster.

This lens's upmarket build quality includes weather seals and a robust and rugged feel, along with a dirt-resistant coating on the front element. Other attractions in this lens include Extra-low Dispersion glass, internal focusing and ring-type ultrasonic autofocus.

Sigma APO 70-200mm f/2.8 EX DG OS HSM

• Sigma APO 70-200mm f/2.8 EX DG OS HSM review

Sigma's fixed-aperture mid-range zoom is a long-standing favourite, and it can be used on both full-frame cameras and APS-C format D-SLRs – on APS-C cameras the focal range effectively becomes 105-300mm. The Sigma shows that third-party lenses aren't always the poor relations – the best can give more features and more performance for your money.

The Sigma is under half the price of the Nikon and £1,200 less than the Canon equivalents. Inside the lens are two FLD (F Low Dispersion) elements, claimed to equal top-quality fluorite glass in performance, as well as three SLD (Special Low Dispersion) elements, plus Super Multi-Layer Coatings. The aim is for excellent sharpness and contrast, with minimal color fringing, ghosting and flare.

Sigma APO Macro 180mm f/2.8 EX DG OS HSM

• Sigma APO Macro 180mm f/2.8 EX DG OS HSM review

This Sigma prime lens is designed for macro photography, but its focal length and wide maximum aperture make it an excellent telephoto lens too. The 180mm focal length and f/2.8 maximum aperture are ideal for low-light sports/action photography as well as tight close-ups. It can be used on both full-frame cameras and APS-C models, where the smaller sensor size means it effectively becomes a 270mm f/2.8.

Like most macro lenses, the Sigma has a long travel distance in its manual focus ring to enable precise close-up focussing. It's surprising, then, that the autofocus is so fast, snapping into focus even over large changes in distance. There's a three-position focus limiter switch, for locking the autofocus range to either end or enabling full travel.

Sony FE 70-200mm f/4 G OSS

• Sony FE 70-200mm f/4 G OSS review

This is a high-spec telephoto zoom designed for the full-frame Sony Alpha A7 range. Sony needs to keep rolling out new lenses to boost the appeal of its full-frame compact system cameras, so this is a welcome addition. While A7 cameras are slim compared with SLRs, there's nothing small about this lens. It's every bit as big and heavy as similar lenses for full-frame DSLRs, weighing in at 840g.

The Sony is dust and water-resistant but lacks the weather-sealed mounting plate of many competing lenses. There's a set of switches for AF/M focussing, an autofocus range limiter, on/off for the optical stabilizer, and mode 1/2 for static or panning stabilization. The Sony also has a similar off-white paint job to Canon's pro telephoto lenses.

Tamron SP 70-200mm f/2.8 Di VC USD

• Tamron SP 70-200mm f/2.8 Di VC USD review

The Tamron SP 70-200mm f/2.8 proves you don't have to go for a maker's own lenses to get top-quality performance. It's designed to work on both full-frame DSLRs and APS-C format cameras, where the focal length is equivalent to 105-300mm. The 'SP' denotes one of Tamron's 'Super Performance' lenses, and it joins another of our favorites, the Tamron SP 24-70mm f/2.8 Di VC USD.

The 70-200mm has a truly professional feel with weather seals, fast ring-type ultrasonic autofocus and Tamron's proprietary Vibration Compensation optical stabilizer (though the stabilizer is omitted from the Sony version).

Our verdict

There's no denying that 70-200mm f/4 lenses are smaller and more lightweight than their f/2.8 counterparts. However, denying yourself that extra f/stop in aperture width can feel like a compromise, and a step down the quality ladder.

That's why the Tamron 70-200mm f/2.8 is so impressive. It features a weather-sealed build, super-fast autofocus and excellent optical stabilization, at a very affordable price. Indeed, it costs only a little more than the Canon and Nikon f/4 zooms. Best of all, the Tamron delivers stellar image quality throughout its entire zoom range and right into the corners of images. For our money, it's simply the best option in its price bracket for Canon, Nikon and Sony (A-mount) cameras.

The Sigma 70-200mm f/2.8 is another appealing lens, and at a pretty astonishing price – some £300 cheaper than the Tamron. However, the lens lacks any weather seals and doesn't maintain such excellent sharpness at its widest available f/2.8 aperture, or at the long 200mm end of its zoom range.

If size and weight matter more to you than an extra f/stop, the Canon and Nikon 70-200mm f/4 lenses are both very good and sensibly priced, with the Canon leading the way for sharpness. At the other end of the scale, the Sigma 180mm f/2.8 is the biggest and heaviest lens in the group, as well as being the most expensive. But if you're in the market for both a fast telephoto prime and a great macro lens, it does both well.

from TechRadar: All latest feeds http://ift.tt/1Dplcoh

via IFTTT