Macro lenses explained
With practically all compact cameras offering close-focusing capabilities, and an abundance of lenses to suit all budgets, getting into macro photography today is as easy as it is enjoyable.
Thanks in part to the availability of cheap filter-like lenses, extension tubes, and other accessories, photographers are able to dabble with close-up shooting with minimal outlay, before they decide whether to take things more seriously with a dedicated macro optic.
The eight macro lenses on test here are all respectable candidates for that next step up, and each combines a useful medium telephoto focal length with a wide maximum aperture, making them suitable for more than just close-up flower and insect shots.
Before we pit them against each other to see which is the best macro lens, though, let's take a closer look at the technical aspects of macro lenses.
A true macro lens is one that can capture frame-filling images of subjects that are the same size as the sensor itself. Manufacturers often show this by stating that a lens has a reproduction ratio of 1:1. Today, the term 'macro' is more widely used to describe equipment with some sort of close-focusing capability, and lenses with up to 1:4 magnification ratios (quarter life size) are often billed as having macro functionality.
Whether a macro lens is used on a DSLR with a full-frame or a cropped sensor, its magnification ratio remains the same. The subject is still, after all, being captured on the sensor at the same size; it's just that the smaller sensor has the effect of cropping the image. Therefore, to fit it into the frame you have to compose your shot further away from the subject.
Unlike macro zoom lenses, which attempt to offer close-focusing together with an expansive focal range, fixed focal-length macro lenses are optimised for only one focal length, and specifically for close-up shooting, which makes them a more desirable option.
These typically fall into one of three focal-length ranges, the shortest being around 40-60mm and the longest comfortably in telephoto territory at around 150-180mm.
The macro lenses on test
All but one of the eight macro lenses on test are in the mid-telephoto, category, which is around 90-105mm, and the only lens that isn't – the Olympus Zuiko Digital ED 50mm 1:2.0 Macro – is designed for bodies on which its effective focal length becomes 100mm.
The pricing of these lenses is consistent with their focal length, being higher than shorter macro optics and lower then longer ones, but the cost still varies. The image stabilisation systems in both the Sigma 105mm f/2.8 EX DG OS HSM and the Nikon AF-S VR 105mm f/2.8G IF-ED partly explains why these are the second and third most expensive options here. Other variables include autofocus technology and whether the lens is capable of focusing internally.
The latter point is important for macro shooting because it means that a lens can focus without its inner barrel extending outwards. This prevents the lens inadvertently touching the subject, and reduces the likelihood of shadows from the lens being cast over the subject.
It's also worth bearing in mind that a longer lens will typically have a longer minimum focusing distance than a shorter lens.
The shallow depth of field obtainable with longer lenses also means that it's easier to separate your subject from its background, although considering just how shallow this can be, shooting at the wider apertures may be unfeasible for much macro work.
It's advisable, therefore, to set a smaller aperture when shooting very close up, to ensure the entire subject is in focus.
The lenses on test focus from very close up to infinity (much of their focusing range isn't used when shooting close up), and it can take a while for a lens to work through this entire range when it seeks to focus on a subject. Fortunately, many macro lenses feature focus limiter switches, which can be used to close off a part of the range that isn't required, allowing focus to be acquired sooner.
Although the lenses on test are designed primarily for macro photography, they can be used successfully for other genres. The eight on test are high-quality medium telephoto lenses, each claiming to be corrected for distortion and chromatic aberration, and designed to record a high level of detail.
On bodies with full-frame sensors their focal lengths are particularly suited to portraiture. On bodies with APS-C or smaller sensors they can be used for many types of nature photography, because their relatively wide maximum apertures help to isolate subjects from their backgrounds and maintain fast shutter speeds.
Their low distortion also means that they can be useful in product photography too, while food photographers are also likely to appreciate their maximum aperture and focal length.
Macro lens construction and features
Macro lens construction
By definition, macro optics are designed for close-up shooting. If you look at their optical construction, you tend to find symmetry in the arrangement of the elements.
The design towards the front of the lens is typically repeated in reverse towards the rear. This's so that the rear elements cancel out some of the aberrations caused by the front elements. Greater correction is required as the magnification factor increases.
Another common feature is the 'double-helicoid' design of the focusing mount. This gives the large focus range required by a macro optic. Floating elements and lens groups, which move independently within a lens, are also commonly employed to correct spherical aberration, the extent of which varies with distance.
Using floating elements requires a more complex design, which is often reflected in the price of the lens.
Macro lens features
Maximum aperture
Shallow depth of field aside, a wide maximum aperture on a lens, such as f2.8, means it's capable of admitting plenty of light to help keep shutter speeds high.
Distance scale
This shows the distance at which a lens focuses in feet and metres. On macro lenses it often also includes the reproduction ratio, which decreases with distance.
Focus limiter switch
This effectively closes off part of the lens's focusing range, which is useful if you're only shooting close-up and you don't need to focus on distant subjects, or vice versa.
Internal focusing
A lens with an internal focusing system will ensure that it remains at the same physical length while focusing, which is particularly handy if your subject is close to the front element of the lens.
Focal length
Minimum focusing distances tend to rise as the focal length is increased, so longer lenses can be useful when you need to keep a safe distance from a living subject, such as a small insect.
Optical stabilisation
This can be useful if the body you're using lacks a sensor-based image stabilisation system, although if you're using the lens on a tripod for macro work, it's best to turn stabilisation off.
Canon EF 100mm f/2.8 Macro USM
Canon EF 100mm f/2.8 Macro USM - £440
Sharpness test
Despite a little edge softness at f/2.8, the Canon lens does a sterling job to produce sharp images with good consistency across the frame.
Fringing test
Central performance is very good, with only minimal levels of fringing at all apertures, but things start to fall apart towards the edges.
Distortion test
Distortion is low, but it's not quite as low as on some of the others. Overall, its performance is consistent with its price tag.
Images test verdict
Sharpness is sometimes excellent, and consistent. With reasonable control over both distortion and fringing, the Canon's a good performer.
Read the full Canon EF 100mm f/2.8 Macro USM review
Nikon AF-S VR 105mm f/2.8G IF-ED
Nikon AF-S VR 105mm f/2.8G IF-ED - £620
Sharpness test
Sharpness is superb at both its widest and mid-range apertures, but it isn't maintained throughout the frame.
Fringing test
A poor performance, with fringing evident throughout the frame. The fringing at the centre doesn't get too much worse as you travel further out.
Distortion test
Distortion isn't too problematic in real-world images, but overall performance is still less than impressive.
Image test verdict
For sharpness the Nikon is excellent, particularly if you use its widest apertures the most, but distortion and fringing is worse than expected.
Read the full Nikon AF-S VR 105mm f/2.8G IF-ED review
Olympus Zuiko Digital ED 50mm 1:2.0 Macro
Olympus Zuiko Digital 50mm 1:2.0 Macro - £580
Sharpness test
Sharpness isn't that great wide open, with some of the weakest results out of the eight lenses, but at small apertures sharpness is excellent.
Fringing test
The centre of the frame shows low fringing, and although this rises slightly towards the edges, it's kept under control.
Distortion test
The Olympus produces the most distortion in the test, and significantly more than the next worst lens, the Nikon 105mm.
Image test verdict
Control over chromatic aberration and sharpness is excellent overall, and even when you get to the narrowest apertures, results are still good.
Read the full Olympus Zuiko Digital ED 50mm 1:2.0 Macro review
Pentax smc D-FA 100mm f/2.8 Macro WR
Pentax smc D-FA 100mm f/2.8 Macro WR - £480
Sharpness test
Wide-open performance isn't too good, and the improvements between f/8 to f/16 are confined to the centre of the lens.
Fringing test
There's fringing at the centre, and it gets considerably worse towards the edges, but recent Pentax SLRs can correct lateral chromatic aberration.
Distortion test
Distortion control is excellent, with just minimal warping. Were it not for the superior Sigma lens, the Pentax would just edge its way to the top.
Image test verdict
It's a shame that wide-open sharpness and control over chromatic aberration are poor, because otherwise this is a fine, solid lens.
Read the full Pentax smc D-FA 100mm f/2.8 Macro WR review
Sigma 105mm f/2.8 EX DG OS HSM
Sigma 105mm f/2.8 EX DG OS HSM - £700
Sharpness test
Wide-open results are great, and it just gets better from there. That it can come so close to matching the results from the Zeiss is amazing.
Fringing test
Again, second only to Zeiss. There's little central fringing at all apertures, and at the edges it's still better than some lenses at the centre.
Distortion test
A stellar performance, with the best control over distortion out of all the lenses on test, and practically no distortion in real-world images.
Image test verdict
The Sigma lens is consistently sharp, and there are no issues with distortion or chromatic aberration. Its only failings are weaker wide-open results.
Read the full Sigma 105mm f/2.8 EX DG OS HSM review
Sony 100mm f/2.8 Macro
Sony 100mm f/2.8 Macro - £580
Sharpness test
The Sony lens gets off to an unimpressive start at its widest apertures, before sharpening up and doing well at the middle.
Fringing test
Results aren't too bad at the centre of the frame, but as you venture further towards the edges, performance drops off.
Distortion test
Visible distortion in images is low, but measured distortion puts the Sony lens somewhere in the middle of the group.
Image test verdict
There's a lot to like about this lens, but considering its price, it's disappointing that it doesn't provide a consistent performance.
Read the full Sony 100mm f/2.8 Macro review
Tamron SP AF 90mm F/2.8 Di Macro 1:1
Tamron SP AF 90mm F/2.8 Di Macro 1:1 - £355
Sharpness test
At f/2.8 the Tamron lens produces some of the most impressive results, although this is confined to the centre of the frame.
Fringing test
Considering the chromatic aberration it produces in the centre, it's surprising that it doesn't escalate much further at the edges.
Distortion test
Distortion could be improved, with only the Nikon and Olympus lenses faring worse, but it isn't much worse than the next couple ahead of it.
Image test verdict
Despite distortion and fringing problems, the Tamron lens is impressive for its price. Even at its widest aperture, it records excellent central sharpness.
Read the full Tamron SP AF 90mm F/2.8 Di Macro 1:1 review
Zeiss Makro-Planar T* F2 100mm ZE
Zeiss Makro-Planar T* F2 100mm ZE - £1,550
Sharpness test
Despite a slight dip in the corners at f/2.2, the Zeiss records razor-sharp images that are consistently sharp throughout the frame.
Fringing test
As well as being the sharpest lens on test, it's also the most adept at keeping fringing down to a minimum, with only minor traces.
Distortion test
Lab tests show slight distortion, but certainly not enough to require any kind of software-based correction.
Image test verdict
This is a cracking lens, sharp and consistent throughout its range. There's also very little distortion and chromatic aberration.
Read the full Zeiss Makro-Planar T* F2 100mm ZE review
Macro lens performance benchmarks
The macro lenses in our test ranged in focal length between 50mm and 105mm, with all but the Zeiss Makro-Planar T* F2 100mm ZE specifically designed for macro use.
All the lenses have a maximum aperture of f/2.8 – except the Zeiss and the Olympus Zuiko Digital ED 50mm 1:2.0 Macro at f/2 – and a minimum aperture value of between f/22 and f/32.
The lab test results show that all of the lenses perform well for centre sharpness at f/8 and f/16, but at the maximum aperture of f/2.8, the Olympus Zuiko Digital ED 50mm 1:2.0 Macro, Sony 100mm f/2.8 Macro and Pentax smc D-FA 100mm f/2.8 Macro WR lenses all produced visibly softer images, with results considerably lower than those of the other lenses.
The Sigma 105mm f/2.8 EX DG OS HSM, Nikon AF-S VR 105mm f/2.8G IF-ED, Tamron SP AF 90mm F/2.8 Di Macro 1:1 and Zeiss Makro-Planar T* F2 100mm ZE all produce good centre sharpness across the aperture range, with the Sigma and Zeiss really leading the group with sharp results across the entire frame.
As expected from fixed focal-length lenses, the amount of fringing is minimal, with only the Pentax, Nikon and Sony lenses showing mild signs towards the edges of the frame.
Verdict: Best macro lens
The Zeiss Makro-Planar T* F2 100mm ZE is by far the best macro lens performer, with stunningly low aberration and superb, consistent sharpness. But even if it were cheaper, its maximum magnification and lack of autofocus may still be enough to put many off.
At almost £1,000 less, the Sigma 105mm f/2.8 EX DG OS HSM optic does a remarkable job to offer similar performance, recording high detail throughout its aperture range and keeping aberrations at bay, as well as providing the benefits of optical stabilisation and a near-silent autofocus system.
Hopefully, Sigma will provide the lens in a wider range of mounts. In the meantime, Canon and Nikon DSLR users should start saving up for it, because it really is an impressive macro lens.
The Tamron SP AF 90mm F/2.8 Di Macro 1:1 lens can safely maintain the brand's reputation as a good alternative to the big four names. Even so, a bargain lens is often a bargain for a reason, and the noisy, slow focusing motor and lack of internal focusing are its biggest shortfalls.
Its 90mm focal length gives it a shorter working distance than most of the others here. Along with its extending inner barrel, this makes it less than ideal for shooting living subjects.
The Pentax smc D-FA 100mm f/2.8 Macro WR and Sony 100mm f/2.8 Macro lenses occupy similar mid-range performance territory, each providing weak wide-open but respectable mid-range results, and neither having the luxury of an internal focusing system, nor a quiet AF motor.
Despite this, the Pentax has a number of advantages that are particularly welcome at its sub-£500 price point, such as its sturdy metal body and compact form, as well as its weather seals and Super Protect coating.
The Olympus Zuiko Digital ED 50mm 1:2.0 Macro does little to excite with its poor wide-open results, distortion, and 1:2 reproduction ratio, but its good mid-range sharpness, as well as its control over chromatic aberration, go some way to justifying its £580 price tag.
Verdict
The Sigma 105mm f/2.8 EX DG OS HSM takes top honours, despite a strong performance from the Zeiss Makro-Planar T* F2 100mm ZE. With excellent sharpness and superb control over aberration, the Sigma macro lens isn't cheap, but you get what you pay for.
Best for Canon APS-C format users
Sigma 105mm f/2.8 EX DG OS HSM
What's good: excellent sharpness and superb control over aberration.
What's bad: inconsistent when wide-open.
Our verdict: it's not cheap, but you get what you pay for.
Best for Nikon DX format users
Sigma 105mm f/2.8 EX DG OS HSM
What's good: excellent sharpness and superb control over aberration.
What's bad: inconsistent when wide-open.
Our verdict: it's not cheap, but you get what you pay for.
Best for Olympus Four Thirds users
Olympus Zuiko digitAl ED 50mm 1:2.0 Macro
What's good: small and capable of excellent image quality at narrower apertures.
What's bad: Weak wide-open performance.
Our verdict: it's not cheap, but it's a good four thirds option.
Best for Pentax users
Pentax SMC D-FA 100mm f/2.8 Macro WR
What's good: good overall sharpness and excellent control over distortion.
What's bad: no internal focusing.
Our verdict: A small, solid optic with good mid-aperture results.
Best for Sony APS-C format users
Tamron SP AF 90mm f/2.8 DI Macro 1:1
What's good: lightweight and sharp, and a bargain price.
What's bad: inconsistent performance.
Our verdict: A good budget option that exceeds expectations.
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