What is the best 50mm lens for your camera? We put eight of the top 'Nifty Fifty' lenses currently available to the test to see which offers the best combination of image quality and value for money.
Those of us with sufficiently grey hair and elephantine memory might just remember a time when a standard lens for a DSLR had a fixed 50mm focal length.
Indeed, the early zoom lenses of the 1960s often had such dire image quality - loaded with distortions, flare and an almost complete lack of sharpness - that it took a long time for photographers to take them seriously.
Things are different now: it's almost unheard of for an SLR to be sold with anything other than an 18-55mm or similar kit lens. Sure enough, image quality is generally streets ahead of yesteryear's zooms.
They typically deliver a useful range, stretching from wide-angle to short telephoto, and they're usually compact and light in weight.
Faster is better
You can't beat the versatility of a zoom lens, but the compromise usually comes in terms of image quality. While kit zoom lenses and higher-quality standard zooms like the Canon 15-85mm and Nikon 16-85mm can offer good sharpness, distortions can still be a problem.
Vignetting (darkened image corners) can also be problematic, especially when combining short focal lengths with wide apertures. But the biggest drawback, shared by all but the most expensive standard zoom lenses, is that the widest available aperture at focal lengths of around 50mm and beyond is about f/5.6.
So what's so good about having a faster standard 50mm prime lens? For one thing, it enables faster shutter speeds, which can be useful in dull shooting conditions.
For example, where gloomy lighting using the widest available aperture of a kit zoom lens would only enable shooting at, say, 1/15 of a second at ISO 100, a 50mm f/1.4 lens would enable a shutter speed of 1/250 of a second. That's good news for handheld shooting.
Most kit zoom lenses now have image stabilisation built in, or it's available in camera bodies from the likes of Pentax and Sony. The requirement for fast shutter speeds in handheld shooting is no longer paramount, unless you need to freeze the action of people or objects that are moving around.
Even then, given that current DSLRs tend to offer such good image quality at high sensitivity settings, there's always the option of bumping up the ISO when you need faster shutter speeds.
Setting the standard
There's still one thing that a fast prime lens can do that you can't replicate with a typical zoom. The wider aperture gives you a massive reduction in depth of field.
It's great when you want to blur fussy backgrounds (or foregrounds) and make the main object in a composition really stand out. It's particularly good for portraiture, opening a whole new window of opportunity for many SLR owners, which we'll come to next.
A 50mm lens is often referred to as a standard lens. This is because, historically, they give a natural perspective on 35mm film cameras - and the same is therefore true on full-frame digital SLRs.
It gives a nice immediacy to your photography. You see a composition you like, lift the camera to your eye, and shoot without the complexity of adjusting zoom length.
However, due to the crop factor of cameras with APS-C format image sensors, a 50mm lens has an effective focal length of 75mm (80mm if you're using a Canon SLR).
This is absolutely perfect for portraiture, as it enables you to keep an ideal distance from the person you're photographing, so that they can feel comfortable and relaxed, without the camera being too up close and personal.
Another helpful by-product of shooting with a 50mm lens on an APS-C format body is that, along with the increased, effective focal length, the depth of field is further reduced. Again, this is another plus point for portrait photography, but how does it work out in practical terms?
Let's assume you're taking a portrait from a distance of two metres, using a focal length of 50mm (75mm effective). With a typical 18-55mm kit lens, the widest available aperture of f/5.6 would give you a depth of field of 36cm.
Shooting with a 50mm f/1.4 lens at its widest aperture, the depth of field shrinks to a mere 9cm. Focus on the subject's eyes and you'll find that even their ears can be starting to look soft.
The widest aperture of a 50mm f/1.8 lens is two-thirds of a stop slower but, even so, it enables a tight depth of field of just 11cm at a shooting distance of two metres.
One frustration here is that you often can't utilise the widest available aperture to gain a tight depth of field when shooting under bright, direct sunlight. This is because it's likely to require a shutter speed for a correct exposure that's faster than the camera can deliver, even at its minimum ISO setting.
The situation can be easily rectified, however, simply by fitting a Neutral Density (ND) graduated filter to the lens.
Features to look for in a Nifty Fifty lens
There are a number of key features you should look for when choosing the best 50mm lens for your camera. In our infographic below we've identified some of these and explain why they're important.
SEE MORE: DO or Di? Your lens markings explained
Best 50mm lens for your camera: Canon EF 50mm f/1.4 USM
Were money no object, you could get the L-series (Luxury) Canon 50mm f/1.2 lens, but it costs a monstrous £1,170.
At a quarter of the price, the f/1.4 is much more affordable and a mere one-third of a stop slower.
It offers some of the same attractions as the dearer lens, including an eight-blade diaphragm to give a rounded aperture, a focus distance scale positioned beneath a viewing window, and Super Spectra coatings to reduce ghosting and flare.
One bit of downgrading is that the autofocus system is based on an ultrasonic motor, rather than being ring-type ultrasonic.
It's a bit slower and more audible, but quiet nonetheless. Unusually for an ultrasonic motor system, or Micro USM as Canon calls it, full-time manual override is available in One Shot autofocus mode.
This is a feature usually reserved for Canon's ring-type USM and more recent STM (Stepping Motor) autofocus systems.
Build quality and specs are superior to the cheaper Canon 50mm f/1.8, also on test. The mounting plate is made from metal rather than plastic, and the f/1.8 lens lacks a focus distance scale.
Typical of non-L-series Canon lenses, however, there's no lens hood supplied; the optional ES-71 II hood costs an additional £25.
Relatively fast 50mm f/1.4 lenses often fail to give great sharpness at their widest available aperture, and this is no exception. It's pretty good by the time you hit f/2.8 and has a sweet spot at f/8. But even here, sharpness is slightly outclassed by most competing f/1.4 lenses.
Build quality: 4/5
Image quality: 4/5
Best 50mm lens for your camera: Canon EF 50mm f/1.8 II
You can't help but feel that Canon had to cut a few corners to build a lens that sells for just £79. Sure enough, it only has a plastic mounting plate, a basic electric micro-motor for autofocus and no distance scale.
It's feather-light at 130g and feels a little flimsy in the hand. There's one less element in the optical design, compared with the Canon 50mm f/1.4 lens, and the diaphragm only has five blades, as opposed to eight.
The focus ring rotates during autofocus, but this doesn't cause any real handling problems. That's because the focus ring itself is positioned right at the front end of the lens, and it's tiny.
The downside is that manual focusing is quite tricky, not only because of the smallness of the ring, but also because its action lacks any real precision.
At 52mm, the filter attachment ring is also small. This can be annoying for Canon shooters who already have kit zoom lenses like the 18-55mm and 55-250mm.
These both have a 58mm attachment thread (as does the Canon 50mm f/1.4), so a step-up ring will be needed to use existing filters.
Canon claims that the lens's 'virtually circular aperture diaphragm' gives a soft effect to defocused areas in images. However, defocused lights and bright spots take on a pronounced pentagonal appearance in anything other than wide-open shooting.
Looking on the positive side, sharpness and contrast are pretty reasonable for such an inexpensive lens.
Build quality: 2/5
Image quality: 2/5
PAGE 1 - Overview; Canon EF 50mm f/1.4 USM ; Canon EF 50mm f/1.8 II
PAGE 2 - Nikon AF-S 50mm f/1.4G; Nikon AF-S 50mm f/1.8G
PAGE 3 - Pentax SMC DA 50mm f/1.8; Sigma 50mm f/1.4 EX DG HSM
PAGE 4 - Sony 50mm f/1.4 A; Sony DT 50mm f/1.8 SAM
PAGE 5 - Image quality comparison & Verdict
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