HD Pentax-D FA* 50mm f/1.4 SDM AW Lens Review

John Riley reviews the premium HD FA* 50mm f/1.4 SDM AW full-frame fast lens from Pentax, providing MTF & CA test charts along with sample photos and his verdict.

Posted: 25/08/2018 - 12:00

Handling and Features
Performance
Verdict
Specification

Over its long history in lens making, Pentax have more than once pitched in with lenses that take on the very best that the Zeiss and Leicas of this world have had to offer. Challenging the best standard lenses of their day, we have had the Super-Takumar 50mm f/1.4, and the SMC Pentax-FA 43mm f/1.9 Limited, both highly respected and the latter even seen in Leica mount. We now have the HD Pentax-D FA* 50mm f/1.4 SDM AW lens, challenging in size and weight the Zeiss alternatives and aiming perhaps to challenge them in quality as well. Let's see if this has been successful, reviewing the lens here using the full frame 36MP Pentax K-1 II body.

HD Pentax-D FA* 50mm f/1.4 SDM AW Handling and Features

Pentax have always offered fine, compact lenses and the first impression here is that the new 50mm lens is instead very heavy and very bulky, weighing in at a substantial 910g without hood or caps. However, once fitted to the K-1 II, and by easy inference the K-1 as well, it balances amazingly well. It no longer feels or looks out of place, just very well suited. The longer it us used, the more appropriate it feels on the full frame bodies. There is a provided petal lens hood that bayonets cleanly into position. In common with many Pentax hoods, there is a small removable window that enables polarising filters to be rotated whilst the hood is still in position. Within the bayonet fit is a standard 72mm filter thread. The rest of the front of the lens is filled with the large front element, coated with a Fluorine Super-Protect layer to repel grease and moisture. The lens is also coated throughout using Pentax's new HD multi- coating plus their Aero-Bright II nano technology to eliminate flare and ghosting.

The lens has an AW (All Weather) designation and as much of the review period was characterised with lashing rain this proved to be very useful and absolutely up to the job.

The only rotational control is the manual focus ring, which continues to be operational during AF. This QuickShift feature enables fine tuning of the focus position when AF has locked on. Behind this is the plastic window that reveals the distance scale, clearly marked in feet and metres. There is no IR correction mark and no depth of field scale. There is an AF/MF switch. AF is achieved using a new, more powerful SDM (Supersonic Direct Drive) Motor and this is fast, silent and very accurate. Focusing is down to 0.4m, or 1.31 feet, giving a maximum magnification of 0.18x, very slightly closer focusing than traditional lenses. The lens uses Internal Focusing and therefore does not change length.

The Pentax K mount here finds itself in the form of version KAF4, enabling the use of the electromagnetic diaphragm of 9 rounded blades. This offers more accurate, quieter stop down, a benefit to both stills and video photographers. This new system requires a compatible body, if necessary via a firmware upgrade. Compatible bodies are the K-1, K-1 II, K-3, K-3 II, KP, K-70, K-S1 and K-S2. Other models will only be able to use the lens at open aperture.

HD PENTAX-D FA* 50mm f/1.4 SDM AW Sample Photos

Optical construction is 15 elements in 9 groups, a long way from the traditional 7/6 construction. There are also 3 Anomalous Dispersion and 1 Aspherical elements. Clearly a serious bit of glass. The bayonet mount is the usual Pentax quality, secured in this instance with no less than 7 screws. Many lenses have only three screws to retain their mounts, so hopefully this is indicative of a very strong and long lasting mount for this heavy lens.

There are no handling issues – the lens operates flawlessly and is a total pleasure to use. AF is fast, balance is excellent and the all weather construction gives confidence to keep on shooting regardless of the weather.

HD Pentax-D FA* 50mm f/1.4 SDM AW Performance

Looking first at sharpness, the centre is excellent from f/1.4 to f/5.6 and very good thereafter from f/8 all the way through to f/16. The edges are excellent from f/1.4 to f/4 and thereafter very good from f/5.6 to f/16. The evenness from edge to edge is commendable, at levels of sharpness very close to those of the Zeiss Otus 55mm f/1.4. The lens can be confidently used throughout its aperture range and in this context perhaps not including f/22 as an option helps to ensure the highest possible quality throughout.

HD PENTAX-D FA* 50mm f/1.4 SDM AW MTF Charts

CA (Chromatic Aberration) is very well controlled, the centre especially so. In general shooting CA does not seem to be a problem, even in demanding situations such as branches against bright sky or the shot of the Astley Green head gear.

HD PENTAX-D FA* 50mm f/1.4 SDM AW Chromatic Aberration Charts

Distortion is virtually zero. For the pedantic in us, it can be measured at +0.01% pincushion, but that is as near to zero as makes no practical difference.

Bokeh is nice, very nice. The out of focus areas are smooth as silk and add to an overall “look” that characterises the best lenses – that is, giving the lenses a character, a visual feel to them that can't be measured but gives that extra something that lifts the images. It is this elusive quality that can make the difference between a favourite lens and one that lives permanently tucked away somewhere.

HD PENTAX-D FA* 50mm f/1.4 SDM AW Aperture Range

Flare resistance is also very impressive and in fact no evidence of flare could be found.

There is a degree of vignetting, -1.3 EV at f/1.4 and f/2, dropping to -1.1 EV thereafter and not improving all the way down to f/16. This can be corrected in-camera or by other software should it be felt necessary.

Value for Money

The HD Pentax-D FA* 50mm f/1.4 SDM AW is priced at £1199, which compared to many 50mm f/1.4 lenses may seem very expensive. However, when we consider at what quality point it is pitching, then things look rather different.

• Zeiss Milvus 50mm f/1.4, £999
• Zeiss Otus 55mm f/1.4 Apo Distagon T*, £2899
• Nikon AF-S Nikkor 58mm f/1.4 G, £1349
• Sony FE Planar T* 50mm f/1.4, £1449

Against those lenses, the Pentax looks excellent VFM. Having said that, there are a large number of alternatives at much lower prices, although they are very different sorts of lenses.

• SMC Pentax-FA 43mm f/1.9 Limited, £579
• SMC Pentax-FA 50mm f/1.4, £399
• Canon EF 50mm f/1.4 USM, £384
• Sigma 50mm f/1.4 DG HSM Art, £599
• Nikon AF-S 50mm f/1.4G, £449
• Sony 50mm f/1.4, £299
• Zeiss 50mm f/1.4 T* Planar, £559
• Samyang 50mm f/1.4 AF, £499
• Samyang 50mm f/1.4 AS UMC, £340

There are also many extremely low cost options on the market, commonly referred to as “plastic fantastics”. In summary, the rating given for VFM reflects the Pentax lens against its peers, that small group of very expensive lenses that aspire to quality without compromise.

HD Pentax-D FA* 50mm f/1.4 SDM AW Verdict

There are plenty of 50mm f/1.4 lenses, although many of them have designs that date back possibly decades. There is nothing intrinsically wrong in this as the 50mm has always been a high quality optic, generally considered the perfect standard focal length for 35mm format. However, things move on, and even higher standards are now possible, albeit using complex designs and being very expensive to produce.

This new Pentax 50mm f/1.4 SDM AW lens aspires to being amongst the best of the best, and indeed it achieves that and at a price which is still high, but which is highly competitive within its own bracket. Add effective AF and all weather construction where some much more expensive lenses are manual focus only, and Pentax Users have a very enviable package. Obviously users of other marques will need to use the alternatives (notwithstanding any adapters that may be available), but Pentax enthusiasts can be confident that they can share too in the very latest quality optical designs.

Specifications: HD PENTAX-D FA* 50mm f/1.4 SDM AW
General
Focal Type	Standard
Lens Mounts	Pentax K
Availability
Year announced	2017
Discontinued	No
Dimensions
Diameter	80mm
Height	106mm
Weight	910g
Construction
Weather-sealed	Yes
Groups	9
Elements	15
Blades	9
Lens
Maximum magnification	0.18x
Internal focusing	Yes
Stabilised	No
Filter Size	72mm
Min Aperture	f/16
Max Aperture	f/1.4
Angle of View	47°
Focal Length	50mm
Focusing
Focusing modes	Autofocus, Manual
Macro	No
Min Focus	40cm
Box Contents
Box Contents	Lens Hood: PH-RBB72, Lens Cap: O-LC72, Lens Case: S120-140, Lens mount cap K

Members photos with related tags: 50mm

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