This is an unusual and impressive beast. Unusual because of its unusually wide aperture for the focal length (except at an enormous price) and certainly for a 135mm lens which is what it effectively is, its SSA (Super-Sonic Actuator focus motor, similar to the systems used in some Nikon and Canon lenses), its inclusion of a focussing distance scale and a limited depth of field indicator, the latter two rarely seen on lenses designed for use on digital cameras. It is also unusual in that it differs from most other Samsung lenses in having most of its body constructed of metal; most others use either completely plastic bodies or have a minimal amount of metal. The weight and bulk of this lens and the need for a very stable construction due to the sheer size of its components, demands a more substantial construction. It is impressive because of its maximum aperture and its size, large for an APS-C camera. The mount is the standard metal one used throughout the current range (one exception being the very lightweight but optically heavyweight 20-50 alternate kit lens); a plastic one would make no sense.
Described by Samsung as ideal for portraiture, its effective focal length is closer to one of 135mm in 35mm camera terms which is normally considered too long for studio use and suitable for head and shoulder shots only at mid-distances (3-4 metres). The ideal portrait lens on a 35mm camera was always considered to be one about 1 2/3-2x that of a standard lens, hence 85mm (or the occasional 90mm) to 105mm were most often described as portrait lenses. For APS-C cameras, such as the NX range, you would need to reduce those values by around one third and therefore 55-70mm would be the range for an ideal equivalent. The nearest existing lens within the Samsung range is the 60mm macro, but its performance is slightly disappointing towards the corners.
The format for this lens is well established and apparently popular as several manufacturers offer a version for their own cameras (a few for the independents) with identical or similar basic specifications, although the number of elements and construction will vary, as will length, weight and filter size. Some include image stabilisation (some cameras have in-body IOS so don't require it in the lens) and internal and automatic focusing, but not all. They all share a short, barrel-shaped format similar to this and most will see a buyer spending £900-1200 for a sample. At these prices, the lenses are usually clearly labelled and advertised as a premium or professional grade product.
Any lens with an aperture this large is going to have a fairly limited depth of field, regardless of its focal length, and an 85mm will have rather little. Were you to focus on someone's eye when they are full-face towards the camera and focus on the eyes, the nose, cheeks and lips will all be out of focus as will the forehead and chin but more so if shooting at the two or three widest apertures. In real-life use and in reasonably bright light, you will probably not want to use apertures wider than f4-5.6 in order to have some depth of field and a small margin for error. Indoors or in poor lighting, the wider apertures will increase the chance of a shot. Because of this issue, the lens allows automatic focusing, but then to tweak the point of focus by rotating the focusing ring without first disengaging auto-focus. You don't have to use the feature but it would be silly not to.
This is an exceptionally sharp lens, but only in the right hands and with the lens-camera unit stabilised in some way. Supporting the camera body on a tripod and having the lens hang from a non-metal camera body is NOT the ideal solution. It may demand provision of a tripod mount, perhaps on a revolving collar, which it unfortunately lacks. It is also a heavy lens (over 700g or around 1.5lbs), about 50% greater than both Samsung's 50-200mm and 60mm macro and also very slightly wider than both although it appears much fatter than the zoom due to its squat format. I was allowed by a dealer to briefly borrow the lens together with a used NX100 body, having previously tried others of the range, some of which I later bought although not from him. Frankly, the lens greatly overwhelmed the camera body and it would be little different on my own NX20. The ideal support for the lens, excluding a tripod, would be a monopod fitted with a cradle should you either be able to find or construct one (I had seen one which was made from part of a fishing rod support and welded to a tripod head, although for a very different and physically longer lens). A tree or other solid object may also help stabilise the lens in use, perhaps with a bean bag to help protect it from scratches. It isn't a lens which you would wish to have hanging around your neck for very long, unless as a 'look what I've got' draw for other photographers.
As I did not plan the loan of the lens, even if only for a few minutes, I was unable to run a comparative test against my own 18-55 or 50-200 lenses as I did not have any of my own gear with me - hence the loan of a NX100 body. Had I ran an organised test under more optimal conditions, I would have shot a series using each lens in turn on one or a small range of subjects. I was unable to do that! I have seen the results of an independent reviewer's test where he did precisely that against the 18-55 alone and the lens is a huge leap and a jump sharper than the standard kit lens which itself produces very good performance for a zoom. That review also stated that the lens' performance wide open exceeds Nikon's famed 85mm f1.8, which is no mean feat in itself, and beats it at every stop. I had used an older version of that Nikon lens with Nikon's F series of cameras and it was bitingly sharp and the current version is supposedly improved thanks to its advanced formulation. For Samsung to achieve a higher level of performance than a lens with one of the best reputations deserves far greater recognition and success for its cameras and lenses. As several other independent reviews are exceptionally positive about the lens, should you choose to buy one, you can expect the same excellent results.
For regular if not everyday use, the focal length may have made more sense in a lighter and potentially more holdable f/1.8 or f/2 format, although I can understand the company's desire to join the 85mm f1.4 club. As it stands, its depth of field wide open is very minimal hence the need to ensure absolutely perfect focus, in a portrait setting probably on an eye or both eyes where possible. Performance wide open is surprisingly very good and improves only slightly when stopping down 1-2 stops and is highest at around f5.6. Obviously, the lens can be used in rather poor lighting conditions and, on the NX20 with its 12800 ISO setting, will open up many possibilities which would otherwise be impracticable. At a more modest 800 or 1600 ISO where the camera's colour and noise performance is still very acceptable if not quite its best, it will allow photography in many situations than perhaps would the slower 50-200mm zoom. Unsurprisingly, there is no obvious geometric distortion (pincushion or barrel) and I would not really expect there to be anything significant at this focal length. I was unable to check for any visible fringing; it was a dull day and there was nothing much to photograph against the sky where it is usually easiest seen.
The lens includes Samsung's iFn system, as do most others in its range, for those who use it regularly. If not previously mentioned, focussing is performed internally and the length of the lens remains completely constant. The front element does not rotate during focussing and use of a polariser or any filter requiring consistent alignment is made much easier.
Its focussing speed on the FX100 appeared almost the same as with other Samsung lenses that I own or have used and does not show any apparent speed improvement. The weight of the lens' internals may demand a different approach than any that Samsung employs on most other lenses in the range, but there does not seem to be any significant gain on offer by this system. However, the NX100 is clearly a very different body than the NX20 and the lens' performance on the more recent body may be very different. As I since placed an order for the lens, I will be able to check this later. The focus distance scale is a useful and welcome addition, although the wide focussing band (ring is suggestive of something much narrower) is excellent if focussing manually or when tweaking fine focus. A feature of this lens is its ability to offer a greatly magnified screen image for a few seconds should you rotate the focussing ring even slightly. By moving this magnified area around the subject, whichever feature or part of a feature you wanted rendered most sharply can be selected and the focus tweaked for effect. The depth of field guide is somewhat limited as it is offered only for f/22, although there would be a decrease in separation of the markings for each wider aperture and the lines will be closer together and probably merge. The proximity of the existing markings suggests a rather coarse focussing action.
The filter mount is 67mm which can be expensive if you need several plus a polariser unless you have other lenses with a similar fitting. The lens comes with a hood, plastic as usual and tubular in this instance which engages with the lens body by a bayonet fitting. It can be reversed and stored over the lens when not in use.
You cannot expect any lens of this specification and performance to be cheap. Samsung have pulled a few design fingers out of the bag to build a lens with this level of performance and which sells at a relatively modest price (Nikon's 85mm 1.4 will cost almost £1000 and Sony's Zeiss-designed Alpha-series equivalent about the same). Canon and Sigma also have their own versions with similar specs and there are others. The lens is possibly aimed at the very serious amateur but more likely at the professional user. Therein lies the incongruity; Samsung's cameras are currently unlikely to be considered by many professional photographers. It took Fuji several years to achieve some acceptance but it is still relatively minimal. Sony does barely better despite its Minolta/Konica inheritance and a wider range of lenses including some which are Zeiss-designed. Samsung has a limited presence in years as a photographic brand and may be seen as a consumer electronics manufacturer, its cameras and lenses not to be taken too seriously. Panasonic was seen in an identical way and its cameras needed several years, use of the Lumix brand name and an association with Leica to gain any credibility. That may be something for Samsung to consider although its pricing is at a more realistic level than some brands.
This is a lens whose price will probably preclude it from being an impulse buy. For its performance alone, it is a bargain even at full RRP. Offering outstanding build quality and performance, this is a lens that stands aside of any other in the Samsung range, not least for its price and weight. It will be a considered purchase for most potential users, not many of whom could use it to full advantage.
Deserving of the highest possible recommendation.