On Trial: Tamron 70-210mm F4.0 Di Vc Usd
Tamron remixes the ‘bread-andbutter’ telezoom to create a lens that combines both affordability and capability in equal measures.
Tamron’s f2.8-speed 70-200mm beyond your budget? How about the new f4.0 70-210mm? That one stop of lens speed makes a lot of difference to the bottom line – as well as the size and weight – yet is hardly an issue in this era of high-sensitivity D-SLRs.
For a long time the perceived wisdom when buying a new accessory lens was to go for the fastest maximum aperture you could afford. This made a lot of sense when the fastest colour films were rated at ISO 1600, but were really still much too grainy and flat for many, making ISO 800 the realistic limit. Many photographers never ventured beyond ISO 400 so large apertures were very handy in lowlight situations, especially when shooting hand-held.
Today, ISO 800 is a standard sensitivity setting for some photographers and, irrespective of sensor size, you can generally range up to ISO 6400 without too many image quality compromises. The best full-35mm sensor cameras are now performing acceptably well a ISO 12,800, 25,600 and even beyond. So, while there are still other good reasons for using a faster lens, seeing in the dark isn’t one of them, and losing a stop or so of lens speed brings other benefits. For starters, the lens can be both smaller and lighter plus, perhaps even more important for some, less expensive. Large-diameter lens elements are still very expensive to make no matter what process is used. So Tamron’s new f4.0-speed 70-210mm telezoom has quite a few attractions, especially if its 70-200mm f2.8 G2 model is a bit beyond your budget.
Let’s do a quick comparison between these two lenses to see what a difference just one stop can make – the f4.0 lens is yours for $1299 versus $2199 (so that’s a solid $900 saved). The f4.0 lens weighs in at just 850 grams versus 1.49 kilos for the 70-200mm f2.8 which is 191.3 millimetres in length versus 174.0 mm. You’ll save a bit on filter costs too, as the f4.0 has a 67 mm diameter screwthread fitting versus 77 mm for the f2.8 lens. Of course, we’re not suggesting the 70-200mm f2.8 lens isn’t worth aspiring to because it’s an exceptional performer, but if you can’t afford it or, perhaps more pertinently, justify spending that amount of money, don’t despair because there’s a very workable alternative now at hand. And, into the bargain, there’s an extra 10mm of telephoto ‘power’ too, which gives an exact 3.0x zoom factor.
in the hanD
The moment you lift the Tamron 70-210mm f4.0 Di VC USD zoom you’ll notice the weight.
It’s not so much that it’s very light, but that it’s not quite the lump of lens you were expecting. This bodes well for hand-held shooting – especially as there’s an optical image stabiliser in there as well – although a tripod-mounting collar is available as a cost-extra accessory which is also the case with Tamron’s 100-400mm. While you’re almost certainly going to need it with the longer telezoom, it’s probably worth living with the 70-210mm f4.0 for a little while to see whether it’s likely to be quite so essential here too.
What’s also immediately noticeable is that, despite the lightweight design and price tag, the 70-210mm f4.0 is still a very well-made lens. Not surprisingly, the barrel tubes are polycarbonate (the mount is stainless steel), but the fit and finish is very good with flush-fitting collars for focusing and zoom which makes for a very clean appearance. Better still, you get full weather sealing with a fluorine coating on the exposed surface of the front element to help repel moisture and dirt. The external manifestation of the weather protection is a beefy rubber gasket around the lens mount
You also get internal focusing and internal zooming so, no matter what the settings, the barrel length always stays the same and the front element doesn’t rotate - which makes a big difference when using orientation-sensitive filters (such as a polariser or ND grads). It also makes for better balanced hand-held shooting as the lens’s centre-of-gravity never changes. Handy too, if you’re shooting through wire fencing.
As on the 70-200mm f2.8 model, the zooming collar is located ahead of the focusing control which is also the same arrangement now used on Nikon’s latest f2.8 lens, but the opposite of its f4.0 model and also Canon’s. The good news for Nikon D-SLRs owners, however, is that the zoom collar rotates clockwise which is the same as any Nikkor zoom. And the range from 70mm to 210mm is fully traversed in a quick 90-degree twist. The focusing collar is mechanical (i.e. not fly-by-wire) so it has quite a positive feel and allows for fairly precise adjustment, although it will continue to rotate past infinity – or the minimum focusing distance – so you have to keep an eye on the focusing scale.
What you don’t get is a focus limiter which can be a great time saver when you’re only working within a known distance range.
There are just two switches on the lens barrel – one for AF/MF switching and one for activating the optical image stabiliser (which Tamron calls ‘Vibration Compensation’). There’s no zoom lock because you don’t need it with this type of zooming mechanism. Tamron says the stabiliser is effective for up to four stops of correction for camera shake. Autofocusing is performed via an ultrasonically-pulsed ring-type drive (‘USD’ in Tamron parlance) with a minimum focusing distance of 95 centimetres. At 210mm, this delivers a maximum magnification ratio of 1:3.1 so, although it can’t really be considered a macro, this lens still has reasonably useful close-up capabilities, even when shooting fairly small objects. Thanks to the ring-type motor, a full-time autofocus override is available by simply turning the manual focus collar.
Dual high-performance microprocessors separately handle the number-crunching for the autofocusing and the image stabilisation which has benefits in terms of the speeds of both. The 70-210mm f4.0 is compatible with Tamron’s optional ‘Tap-in Console’ USB dock which enables firmware upgrades, but also allows for adjustment of the image stabiliser (the operating mode can be changed) and also the responsiveness of the fulltime manual focusing override. Obviously though, this extra control also involves an extra cost, but it’s worth thinking about, especially if you’re regularly shooting certain types of sports.
The zoom’s optical construction comprises 20 elements in 14 groups with three of these elements made from glass with extra-low dispersion characteristics to correct to correct for both axial and lateral chromatic aberrations. The diaphragm has nine blades which gives a more rounded aperture and hence smoother out-of-focus effects. On both the Canon and Nikon mount versions, the diaphragm is electromagnetically controlled which ensures better frame-toframe exposure uniformity with continuous shooting.
We’ve already seen that, mechanically, the Tamron 70-210mm f4.0 performs well for a telezoom lens that is so affordable, and it’s pretty well the same story in optical terms too.
You can’t expect everything for this sort of money so let’s get the main gripes out of the way first. Centre sharpness is good across the focal range, but there’s a fairly marked fall-off towards the corners when shooting at 210mm and especially at the closest focusing distances which is a bit of a pity. Stopping down to between f8.0 and f16 definitely helps, but the corners still look a bit soft no matter what. Otherwise, the uniformity of centre-to-corner sharpness is very good – even when using f4.0 – and certainly with close-up focusing between 70mm and 150mm. Optimum sharpness is delivered between f5.6 and f16. Of course, the corner sharpness is a whole lot better if you’re using an ‘APS-C’ format D-SLR which turns the Tamron into a 105-315mm (with a focal length magnification of 1.5x)… and still in a very manageable package.
You still get full weather sealing with a fluorine coating on the exposed surface of the front element to help repel moisture and dirt.
Slight focus ‘breathing’ also occurs which results in a small change in the focal length (and so also the angle-ofview and magnification) as the focusing distance is adjusted. The direction of the shift varies according to a lens’s optical design and here the focal length increases as the focusing distance gets shorter (and so decreases as it gets longer). Not surprisingly, it’s most noticeable at the 210mm focal length, but happens to some extent right across the focal range. Most zoom lenses do it (and even some primes) and it’s not so much of an issue with stills photography, but can be annoying when shooting video.
Some brightness fall-off or vignetting is evident when shooting at any focal length with the widest aperture, but it’s markedly reduced at f5.6 and completely gone by f8.0. Distortion is minimal with very slight barrel-type bending at 70mm which becomes slight pincushion-bending by 210mm, but it’s rarely going to be noticeable. Commendably, this lens is exceptionally well corrected for chromatic aberrations which, consequently, are extremely hard to spot anywhere in the frame. Flare can be an issue with strong side lighting, but the supplied lens hood provides effective shading.
We used the lens on a number of Nikon D-SLR bodies, both ‘DX’ (i.e. ‘APS-C’) and FX (full-35mm) format, and the autofocusing was fast and reliable every time. The AF processing and drive are certainly responsive enough to maintain the subject tracking speeds we’d expect with Nikon’s own products. The image stabiliser operation is also fast enough to minimise the jumpiness which can otherwise make viewfinding a bit disconcerting. Just as well, really, because without the Tap-in Console, there’s only the one standard IS mode. The USB dock offers the additional two modes that are available on the 70-200mm f2.8 G2 lens (i.e. for panning – with the lens detecting the orientation – and for engaging IS only for the exposure rather than also when viewfinding).
Add the optional tripod collar and USB dock and the price of the Tamron 70210mm f4.0 starts to creep up, but many potential users may not need either. We tested the 100-400mm entirely hand-held even in very low light predawn conditions, relying on very high ISO settings instead and, being faster, the 70-210mm can easily be flown this way too. And, of course, you can buy either accessory later on.
What you get straight out of the box is a very well-made lens that delivers the very versatile 70-210mm focal range in a package that’s both comfortable and efficient to use. The weatherproofing, optical image stabiliser and pretty good close-up focusing capabilities further add to the lens’s all-round useability. Overall, the performance is solid too, including the autofocusing (as per our experience with Nikon D-SLR bodies) and the level of correction for both distortion and aberrations. Affordability is again the main attraction, but as we’ve seen with a number of recent new lenses from Tamron, it doesn’t come at the cost of too many compromises.
Tripod mounting collar is optional, but given this lens’s excellent hand-holding characteristics, many potential users may not often need to resort to using a tripod. As with the 100-400mm’s optional collar, the mounting plate is an Arca-Swiss type (BTW, the two components aren’t the same).
External design sports a smart matte black finish. ‘VC’ initials in the model name indicate optical image stabilisation is inside (plus, incidentally, internal zooming and focusing).
Exposed surface of the front element has a fluorine coating to help better repel moisture and dirt.
Weather sealing measures include a substantial rubber gasket around the lens mount.