Ultimate guide to lenses
The glass that filmmakers should look to own – and why
Words Adam Duckworth
Cameras come and go, but lenses last forever – so always invest in glass. Those old maxims have been trotted out by image-makers for years, from stills shooters to moviemakers. Like all good clichés, there is a lot of truth in it. But it’s not totally accurate, as clearly a 50-year-old lens with old-school coatings and no autofocus might give a vintage look, but will hardly squeeze the last bit of quality and capability from your 6K wonder-camera, shooting in Raw for viewing on a 55-inch mega TV.
And where once the lens and film stock were pretty much the only ways of affecting the final look of your movies, in modern times the image sensor, codecs and editing are crucial, too.
But buy the right lens and it will give years of faithful service, and make a massive difference to your films. With considerations such as ultimate quality, cost, real-world usability and communication with your camera and editing software, the right lens is a crucial purchasing decision.
To help you through the minefield of different lenses, our guide looks at lots of different types of optics to suit all budgets and users.
Cine primes
If you demand the ultimate quality above all else, then a dedicated cinema prime lens should be top of your shopping list. It’s no coincidence that virtually all big-production movies, from Hollywood blockbusters to Netflix series dramas, are shot on matched sets of primes chosen for their light-gathering qualities and the distinctive look they can give to a film.
The very top-end manufacturers like Cooke offer their primes with different ‘looks’ they can give, from crisp and contrasty to flarey and vintage. Even Sigma has got in on the act with its new range of Classic primes. Then of course there are expensive, anamorphic lenses to give that Cinemascope super-wide look, unique oval bokeh and long horizontal flare streaks. If you have very deep pockets, then many manufacturers offer very pricey options that appease every creative whim.
ImagesMounting a prime cinema lens like a Teen (below) or a Sigma (above) opens up a world of amazing bokeh, shallow depth-of-field and ultimate quality
But for the majority of independent filmmakers who are considering a set of primes, then the best are neutral, multi-purposes lenses with good control of flare. And there are lots of options at lots of difference price points. Some even have mounts that can be changed if you swap systems, which is a very real benefit for future-proofing your purchase.
The benefits of cinema primes are that they usually have fast, large T-stops rather than the f-stop apertures of stills photo lenses. An f-stop is a theoretical number calculated from focal length and the size of the aperture opening, whereas a T-stop is an actual measure of light transmission. So one lens set at f/2.8 might not let the same amount of light through as another that’s also rated at f/2.8 – but a T2.8 setting is consistent across brands and focal lengths.
Cine primes have a lot of aperture blades to give smooth bokeh
Cine primes tend to have a lot of aperture blades to give smooth bokeh, rather than the more jagged look of lesser lenses with fewer blades.
And the aperture rings are often clickless, so you can change T-stop smoothly rather than in set half- or third-stop settings, for the perfect exposure. If you plan to change aperture during a shot, then it’s the only way to avoid the obvious stepped changes in exposure.
The majority of cine primes have fast maximum apertures to allow in a lot of light, and give a correspondingly shallow depth-of-field. This can give a lovely cinematic look, but means getting your scene in focus is crucial and more difficult. To help you control focus, cine lenses have geared rings that are married up to external accessories, such as a follow focus rig. Sets of lenses are typically the same size, so it’s easy and quick to change accessories like rigs, matte boxes and follow focus systems. Of course, this does take time, so using primes isn’t as quick as using zoom lenses.
A huge benefit of a manual cine prime is the long throw of the focus ring, and the very precise, tactile control it gives to the filmmaker. Compared to lenses designed for DSLR photo use, which have a much shorter throw or are often fly-by-wire rather than having a direct mechanical connection, they are much easier to accurately control either with your hand or via a follow focus rig. But for shooting 4K at wide apertures, realistically you need to use an external monitor with accurate focus peaking or other focus tools, to get everything sharp. That’s the price you pay for a cinematic look.
A final benefit of cinema lenses is that they are designed to minimise or eliminate the phenomenon of focus breathing. This is when you change focus and get a change in angle of view – almost like you are zooming. It’s especially noticeable when racking focus from very near to very far subjects, or vice versa. Cinema lenses are designed to avoid this by using different internal focus systems, compared to those typically used on stills lenses.
Cine primes do have some disadvantages, though. Many do not communicate with the camera, so there will be no automatic corrections for aberrations or vignetting. Of course, you need to invest a lot to have a complete set, and it takes time and resource to be carrying the whole kit and switching focal lengths all the time.
And unlike a zoom, where you can set the precise focal length you want for the perfect framing, your prime might not be the exact length you want. They are also not made in the most extreme focal lengths, like fisheye-wide or super-telephoto. For those extremes, you will need DSLR glass.
Premium cine primes
It’s possible to drop ten grand on big-name primes from the likes of Arri, Angenieux, Cooke, Leica or Zeiss, but these are out of the reach of most filmmakers. Of the major camera manufacturers, Canon has the widest range of cine primes. The company offers a full set of stunning EF-mount CN-E prime cine lenses, from 14mm to 135mm in focal length, that are 4K quality for Super35 size sensors in the C-range of cine cameras. Canon also offers a vintage or classic look with its new Sumire primes, but these are vastly expensive so largely a rental option, and they only come in PL mount. A set of seven Canon CN-E primes costs around £18,000/ $24,960, so is a serious investment.
Images The high-end lenses tend to offer the widest focal lengths yet retain optical quality, like the 14mm Sigma (below) or 18mm Zeiss CP .3 (above)
Legendary German lens maker Zeiss does have vastly expensive lenses but also has a range of more affordable glass called Compact Primes. The popular CP.2 range was recently redesigned, and these newer CP.3 lenses are smaller, lighter, more consistent in size and even more high-tech, all without a huge increase in price.
There is a ten-strong range comprising 15mm, 18mm, 21mm, 25mm, 28mm, 35mm, 50mm, 85mm, 100mm and 135mm lenses. All the CP.3 series have a 95mm front diameter and are now all the same size, apart from the 100mm and 135mm telephoto lenses, which are slightly longer.
There are improved lens coatings for sharper images with less ghosting and flare
There are improved lens coatings for sharper images with less ghosting and flare. It’s in the body of the lenses and the internal mechanics that the engineers have spent the majority of their time. The focus ring is very smooth and light-feeling. This means focus motors need less power to operate. Zeiss has fitted the CP.3s with the advanced mechanical focusing design from its Ultra Primes and the ball bearing system from the Master Primes, hence the smoothness. Like the CP.2 range, the CP.3s have user-interchangeable lens mounts available in PL, Nikon F, Micro Four Thirds and Sony E mount.
The CP.3 range comes in standard or XD versions (the latter stands for extended data). The XD lenses cost more – a 50mm version costs £/$ compared to the £/$ standard version.
This buys you Cooke/i data connections and an extra Lemo socket that can output extended lens data on distortion and shading characteristics. Zeiss provides a plug-in software so you can automatically adjust the images in DaVinci Resolve.
Firmly in the premium category are the cinema lenses from Sigma, with the High Speed 50mm T1.5 full-frame prime costing £/$. Coming soon is a range of these lenses with i/Technology, for communication with the camera.
The lenses are all-metal and the 50mm has 13 elements in eight groups, with one aspherical and three FLD elements. These are made from Sigma’s high-end coated glass. As the optical design is shared with Sigma’s range of Art prime lenses designed for DSLR use, it means the glass is produced in higher numbers and the optical development has already been paid for by the stills department. Hence Sigma being able to offer such high-end glass at a price that serious filmmakers can afford.
Unlike the Art lenses, the cine range is housed in a traditional, all-manual metal body with a clickless aperture ring. The focus ring has a 180° rotation for precise control, and both rings use standard 0.8M gearing for use on rigs and follow focus systems.
The other lenses in the Sigma range also share the same position and sizes for the controls, so it’s fast and easy to change lenses between shots – there’s no messing around with changing rigs. The iris has nine rounded blades for a smooth, circular bokeh and it certainly works, as out-of-focus highlights are pleasingly smooth.
There is no discernible focus breathing, so as you change focus the image stays the same size in the frame – a key bonus of a true cinema lens. Other high-end cine primes to consider include the Schneider-Kreuznach Xenon series.
Budget cine primes
A major consideration when buying cine lenses is the sensor size they will cover. Some, like the very affordable Veydra or Kowa ranges, are for Micro Four Thirds sensors such as those in the Panasonic GH5S and Olympus OM-D series. They are small and compact, ideal for the smaller MFT cameras.
All the features of a premium prime cinema lens but at less than half the price: this is the promise Korean lens brand Samyang makes of the Xeen range of super-fast glass for full-frame cameras.
Xeen’s range of cine primes are at the opposite end of the scale to servo-assisted, electronically remote-controlled, parfocal design zooms with built-in image stabilisation and metadata communication. They don’t have any of this, which leaves them with the simple task of completely focusing on offering a pure cinema lens at an affordable price.
All the features of a premium prime cine lens but all at less than half the price
The range is 14mm, 16mm, 20mm, 24mm, 35mm, 50mm, 85mm and 135mm in a family that’s designed for consistency in size and optical performance, in terms of look and colour.
The lens housings are made of aluminium with standard 0.8M ring gearing, but unfortunately there is no weather sealing. Every lens has the same front diameter of 114mm and the gear rings are in the same place, so it’s fast and easy to switch lenses without having to adjust follow focus rigs.
The fast apertures are controlled by a de-clicked ring, and the lenses are available marked in metric or imperial distance scales to suit your preference. They also come in Canon EF, Sony E, Micro Four Thirds, PL and Nikon F fittings.
These may be a budget offering – the Xeen 50mm is £/$, for example – but feel like a quality bit of kit. The bayonet fit is precise with no play, the focus ring has a large, 200° movement that allows for ultra-precise and smooth focusing, with a lovely mechanical feel.
There is some drop-off in resolution at the edge of the frames, as you’d expect, a tiny bit of chromatic aberration and some slight barrel distortion. But in a lens at this price point, the optical performance is very, very good. The bokeh is smooth, although as you open up the lens aperture it does change from circular to slightly egg-shaped. But it’s nothing that would worry most users.
The Xeen’s colours do tend towards a very slight green cast, but this is easily sorted in post production so is not of any real concern. Flare is well controlled. For a more affordable option, they are great performers.
Images Samyang’s Xeen range fits full-frame cameras, whereas the smaller Kowa and Veydra MFT lenses are smaller and even more affordable
Samyang recently revealed a new series of smaller, lighter Xeen primes called the CF range, made with carbon fibre composite in the lens barrel. A Sony E mount version will cost £/$ when they hit the market.
Swiss brand Irix has also recently hit the market with a small but growing range of cine primes that are affordable and good quality. Only three lenses are currently available, but this will expand soon as filmmakers demand a whole set of matching optics.
Cine zooms
If you want all the handling advantages of a cine prime such as T-stops, long-throw focusing rings and de-clicked iris rings, but don’t want to carry a bagful of lenses around, the latest cine zooms might be just what your filmmaking needs.
But there are some disadvantages – the lenses are larger and more pricey than a single cine prime, for example. They also require larger rigs as there is an additional control needed for the zoom ring. Optical quality is slightly compromised as the lens has to perform at various focal length settings, and the maximum aperture is far less than a prime, so super-shallow depth-of-field is far less easy to attain.
Of course, they do offer the advantages of more precise framing, no time wasted changing lenses between shots, and are significantly less expensive than a full set of primes.
Compared to DSLR-type zoom lenses, cine zooms are designed to minimise focus breathing and zoom shift. When zooming a conventional DSLR lens, the focal point shifts so you have to refocus, and often the image skews slightly off centre. This makes reframing slower, and zooming during shooting impossible.
Cine zooms are built to minimise focus shifts and off-axis changes by driving the front focus group and the zoom group independently, either optically or mechanically. Thanks to this, there is no lag of the type you’ll often find with fly-by-wire lenses.
Most cine zooms have a large, 200° focus rotation angle, more than double most DSLR lenses; three mechanical lens rings control the focus, zoom and iris. The iris ring is stepless for greater precision when changing exposure, and as it’s clickless, there is no vibration or noise as you alter settings. Standard cine lenses like follow focus rigs all fit easily due to the 0.8M standard-sized gear pitch on the focus, zoom and iris rings.
At the top end of the cine zoom market is the Zeiss LWZ, which stands for Light Weight Zoom. It’s for Super35 sensors, has a 21-100mm range, weighs 2kg/4.4lb and costs £/$10,400 – so it’s not really light or cheap. However, it is around half the price of Zeiss’s premium cine zooms. It uses all of the legendary Zeiss know-how and build quality, just in a lighter package.
At far more affordable price points are zooms from Sigma and Fujifilm. Sigma has the High Speed Zoom Line to cover the Super35 frames and the full-frame FF Zoom Line, which has a £/$ 24-35mm T2.2 in EF and E mounts. The Super35 High Speed Zoom Line comprises an 18-35mm T2 and a 50-100mm T2 at £/$ each.
The Sigma bodies are all metal construction, with standard 0.8M ring gearing, and are splash and dust resistant – including a weather seal on the EF lens mount. The body is reasonably compact, given the speed of the lens.
Colour balance has been standardised across the range of lenses, as has the 95mm front diameter and the 82mm filter size, plus the ring gear positions.
The focus ring has 180° of travel, the zoom 320°, and the iris has a constant angle between stops. On some versions, the aperture setting is fed to the mount so on suitably equipped cameras you can see the value set in the viewfinder, and it will be recorded, along with zoom and focus information, in metadata.
Compared to DSLR-type zooms, cine zooms minimise focus breathing and zoom shift
Also making a big impact on the market has been Fujifilm, with its two manual cine zooms available in Sony E, Fujifilm X and MFT mounts. Fujifilm’s MK zooms use technology from the firm’s broadcast cine lenses, retaining the optical quality but at lower weight, cost and size.
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