Wide and fast: The Lumix S 18mm F1.8

The new lens matches the exterior design of the other lenses in the Lumix S series of f/1.8 lenses

The Lumix S series of f/1.8 lenses goes from strength to strength as the set increases in the number of focal lengths now available. This new 18mm f/1.8 adds some really wideangle views to a collection of matched lenses that, with this one included, numbers five in total and which from October will cover focal lengths from 18mm to 85mm. The principle characteristics of the lenses in this series so far have been that they are lightweight, small and fast – and that they cost much less than you’d expect. This new 18mm continues the same theme, and remarkably matches the other lenses in the series for image quality as well – which isn’t easy with such a wide angle when you trying to keep it compact.

The new 18mm F1.8 also uses a 67mm thread, so users can use the same filters and accessories across the whole series

The Lumix S series now looks like this:

• Lumix S18mm F1.8
• Lumix S24mm F1.8
• Lumix S35mm F1.8
• Lumix S50mm F1.8
• Lumix S85mm F1.8

As with the previous models, users can customise the behaviour of the focus ring to control the degree of rotation needed in manual mode to shift the focus position as well as how the quickly position is reached

The new lens is designed to physically match the existing lenses, so that the focus ring and the centre of gravity are in the same place to make switching between lenses easy when using a rig and so gimbals need minimal rebalancing. Equally the filter thread matches the 67mm of the other lenses, so filters and matt boxes can be switched without any extra drama.

Small and lightweight, the new S 18mm F1.8 is an ideal match for the Lumix S5 but is equally at home on any of the Lumix S models

As expected, the new lens also runs at the same 240fps frequency of the other lenses in the set, so they can all make the most the AF speed of the camera they are operating on. This ensures not only quick focus acquisition but also confident and responsive tracking when the subject is moving.

The Lumix lens designers have managed to combine a very wide angle focal length with an extremely wide aperture without compromising image quality

It is hard to design a small 18mm lens in which sharpness, colour fidelity and distortion control don't fall away in the corners of the frame, but Panasonic has used a lot of low dispersion elements in this lens to ensure quality remains consistent right into the corners. Of the thirteen elements in the design three are ED (Extra-Low Dispersion), one is UED (Ultra Extra-Low Dispersion) and another is UHR (Ultra High Refractive Index). Between these and the three aspherical elements Panasonic ensures all colours focus accurately to avoid fringing and loss of sharpness, and that straight-edged subjects close to the extremes of the frame are drawn straight and not bowed. The aspherical elements and the UHR element also help to keep the design compact.

Even at moderate apertures we get really extensive depth of field with this wide lens. This was shot at f/8

I used this lens on the Lumix S5 and the S1R and found it’s remarkably responsive and quick to focus. With the 240fps frequency it jumps on the subject without hesitation as soon as you touch the rear screen or just half-press the shutter. Moving subjects are kept as well focused as still ones, and in continuous AF settings the lens keeps hold of the subject easily and with accuracy. Its ability to receive new instructions from the camera so quickly means it can react and respond really quickly.

One of the most pleasing aspects of the lens is the well-controlled curvilinear distortion. When the camera is kept level there are few clues to the wide of the angle of view

It would be normal to find a degree of distortion in a wide angle lens like this, but the S 18mm F1.8 is remarkably distortion-free, so straight lines close to the edges of the frame remain straight – which is an impressive achievement. There’s hardly a hint of barrel distortion at all which is brilliant news for architectural photographers as well as anyone who wants their images to look natural.

Although it’s harder to achieve a shallow depth-of-field with a wide angle lens, the f/1.8 maximum aperture of this model gives us that opportunity even when the subject isn’t really close to the camera

Performance even at the widest aperture is excellent, so we are free to use the f/1.8 setting in low light or when we want to draw attention to our subject with a shallow depth-of-field. And the lens is capable of achieving impressively shallow depth-of-field even when the subject isn’t especially close. The nine-bladed iris renders out-of-focus areas really very nicely indeed, and offers us a smooth transition from focus to out-of-focus – which helps to emphasis the feeling of selective-focusing by make out-of-focus areas appear more out-of-focus. Lenses this wide don’t always have as many aperture blades as the nine in this one, and the roundness of the iris makes a significant difference to the look of images shot with the aperture closed down.

The amount of detail the lens can render is very impressive. This close-up frame was recorded at f/4.5 on the Lumix S1R and is absolutely packed with information

Sharpness is first-rate right across the frame too, so we can feel confident putting our subject close to the edges of the frame and know that details even in the corners will be rendered well. Obviously corner performance is more important to stills photographers as most video will be recorded in a 16:9 aspect-ratio that removes corners, but anyone shooting open-gate will be glad of it. I tested corner resolution using the 47MP of the S1R just to be sure.

With a focal length as wide as 18mm, and an angle of view of 100°, it’s easier to fit large buildings into the frame in relatively tight shooting locations

As hard as it is to make a really high quality wide angle lens that’s small and lightweight Panasonic has really delivered with this 18mm F1.8. It fits in with the existing lenses perfectly and is as sharp and detailed as the best of them. Users can be confident that switching focal lengths during a film or a photo set will result only in a shift of viewing angles, not of colour, sharpness or distortion characteristics, allowing the viewer to concentrate on what they are being shown instead of being distracted by technical inconsistencies.

With the aperture closed to f/16 the S 18mm F1.8 produces very attractive sunstars while still retaining excellent resolution. There’s not very much flare in this shot either

With its low distortion the lens is well suited to a massive range of applications for both film and stills, and will be as at home filming a static landscape as it will recording fast-moving action close to the lens. Although its size and weight make it an ideal companion for the diminutive Lumix S5 it is more than up to working with the demands of the S1H, BS1H and S1R, and brings to this series a really useful focal length at a very reasonable price.

Small and lightweight, the Lumix S 18mm F1.8 makes an ideal lens in a simple handheld rig for videographers

For more information see the Panasonic Lumix website page for the Lumix S 18mm F1.8 lens