SMC Pentax-FA 43mm f/1.9 Limited Lens Review

Features
Handling
Performance
Verdict
Specification

This is the second of the three Limited lenses from Pentax, originally designed for film and aiming to be of the highest manufacturing and optical standards. The 43mm was actually the first to be released, alongside the MZ-3 film SLR in 1998. It was the first total rethink of the design of the standard lens for decades and has a reputation for outresolving even the Carl Zeiss Planar 50mm lens. Now we shall see how it stands up to the very high standards required by today's DSLRs.

SMC Pentax-FA 43mm f/1.9 Limited Lens: Features

The standard lens for a given format is usually taken to be the diagonal measurement. In the case of 35mm film that would be 43mm, hence the logic of providing a 43mm lens. Comprising 9 elements in 7 groups this would suggest a very high level of corrections. On DSLRs this 43mm of course is a 35mm-equivalent of 64.5mm, a relatively unusual focal length.

Although not a telecentric design, where the exiting light rays are as parallel as possible, as we are using only the centre of the field for APS-C sensors this may not prove to be a problem.

The lens is diminutive in size and weighs just 155g, despite its metal construction. The finish is of a very high standard, with beautifully rendered engraving of a very superior sort. The lens cap is a deep metal push on design, again in aluminium, and is lined with plush green velvet. It fits snugly and securely onto the rim of the provided metal lens hood. This hood is deep and effective and can be considered an integral part of the lens. It can be removed to allow the fitting of 49mm filters.

There is an aperture ring on the lens and coverage is full frame. For the DSLRs the ring is set to “A” to allow full functionality.

SMC Pentax-FA 43mm f/1.9 Limited Lens: Handling

The lens is compact and a beautiful object in its own right. There is quality engineering here that can be appreciated for its own sake. The Limited description refers to the lens being hand assembled, which means lower production numbers but potentially a very superior product.

The distance scale is viewed through a cutout as per the old M series design, and there is a depth of field scale complete with infra-red focusing mark. Manual focusing is possible via a thin rim that is nicely damped. This is the feel of new technology and is not the same silky smoothness of older conventional lenses. However, it works perfectly well.

Quick Shift was not part of lens design in 1998, so this new feature of Pentax lenses is not available here. Nonetheless focusing is sharp and accurate on the K-5 and images snap quickly into focus.

SMC Pentax-FA 43mm f/1.9 Limited Lens: Performance

We start with considering the rather unusual focal length, at least in terms of the DSLR. This ends up being a very long standard lens, or indeed a very short telephoto. Despite that, it does prove in the field to be quite a versatile length, allowing a modest degree of selection to a subject. It is just long enough to allow distortion free portraits at reasonably close distances.

Chromatic Aberration chart
		Looking at the graphs, Chromatic Aberration is superbly controlled at the centre of the field, but despite the crop sensor becomes visible by the corners. This is a consequence of CA not being such a perceived problem on film. However, fortunately, even at the corners most subjects do not show much fringing. In practice it is acceptable.

Flare is not a problem for Pentax SMC coated lenses. Distortion is around 1% barrelling, well within acceptable limits for a non-macro lens and much better than many zoom lenses.

MTF50 chart
		The MTF50 graph describes the fine resolution of the lens and it acquits itself very well indeed. Corrections are heavily biased towards the centre at larger apertures, but this evens up across the field as we stop down and gives a best performance overall at f/4 and f/5.6. There is a classic rise and fall pattern to the graph and this is clearly a high quality lens.
MTF20 chart
		The MTF20 graph tells us more about contrast and impact. This is the bite of the lens and where the 43mm excels. The performance is even, it peaks at high levels at f/4 and f/5.6 and will result in punchy images full of impact.

This is borne out in practice and where more colourful descriptive language comes into this review. The lens has character, call it fine bokeh, and a certain “something” that lifts it beyond the literal reproduction of a scene. Skin tones are very flattering, texture is excellent and architecture is rendered accurately. Beyond the technical aspects and the cold figures, we have a lens with some life and quality about it.

Fairly tame wildlife can be approached successfully without the animal feeling too crowded, ISO200, 1/320, f/8, 43mm (35mm equiv: 64mm)		Landscape shots show good sharpness and detail, ISO200, 1/80, f/8, 43mm (35mm equiv: 64mm)
Close portraits show no distortion thanks to a reasonable working distance, ISO200, 1/320, f/5, 43mm (35mm equiv: 64mm)		Compact lenses are a boon for travel photography, ISO200, 1/750, f/8, 43mm (35mm equiv: 64mm)
A selective composition looks natural and shows that the 43mm is not too long on digital, ISO200, 1/320, f/8, 43mm (35mm equiv: 64mm)		The 43mm focal length on digital is unusual but allows for tight crops, ISO200, 1/350, f/8, 43mm (35mm equiv: 64mm)
A comfortable working distance allows good communication with the model, ISO200, 1/250, f/5, 43mm (35mm equiv: 64mm)		CA is visible to some extent at the corners of the image, but is not intrusive, ISO200, 1/1000, f/8, 43mm (35mm equiv: 64mm)

SMC Pentax-FA 43mm f/1.9 Limited Lens: Verdict

Although a fairly unusual focal length for APS-C DSLRs the 43mm proves to be a versatile lens with excellent imaging properties. It is fairly expensive, but suggests comparison with Leica quality at a fraction of Leica prices. In this sense it is good value for money. It will be appreciated most by those who need a lens capable of producing large prints or the highest quality for magazine reproduction. It is compact, ideal for travelling light, and has a superior rendering to say the 50mm f/1.4 FA lens.

A beautifully made lens capable of superb results.

SMC Pentax-FA 43mm f/1.9 Limited Lens: Pros

High quality of construction
Compact
Built on lens hood
High quality results
Fast maximum aperture

SMC Pentax-FA 43mm f/1.9 Limited Lens: Cons

High Price

FEATURES
HANDLING
PERFORMANCE
VALUE FOR MONEY
OVERALL

SMC Pentax-FA 43mm f/1.9 Limited Lens: Specification